Thermal Process Research Articles

Fabrication of Anode Functional Layer By Reactive Sputtering for Large Area Thin-Film Solid Oxide Cells

Solid Oxide Cells (SOCs), the electrochemical device that converts chemical to electrical energy, or electrical to chemical energy, have been highlighted for its high efficiency, fuel flexibility, and reversible operation modes between fuel cells and electrolyzers. Recent research has focused on developing intermediate-temperature SOCs (operating between 500 ~ 700°C) to address issues such as thermal durability, and cost. However, reducing the operating temperature presents challenges including decreased rates of charge and ion transport. Consequently, fabricating thin-film SOCs (TF-SOCs) constructed on porous anode supports helps maintain adequate power density even at lower temperatures.Traditional anode supports, however, present limitations in fabricating thin electrolytes due to their rough surface topographies and large pore structures, inherent to powder-based processing methods. To overcome these challenges, vacuum deposition techniques have emerged as alternatives, offering precise control over micro to nanostructures. This precise control enables the smoother layer, referred to as anode functional layers (AFLs), characterized by finer grain sizes. The fabrication of nanostructured AFLs (n-AFLs) enhances the triple-phase boundary (TPB) length, charge transfer, and overall electrochemical kinetics of the cell.Despite these advancements, scalability remains a critical problem that prevents the commercialization of SOCs with optimized AFLs. One of the physical vapor deposition techniques, sputtering, attracts attention due to its scalability, reproducibility, and compatibility with multilayered designs. Reactive sputtering allows the deposition of composite materials by introducing reactive gases during the deposition process.In this study, we fabricated a large-area (12cm x 12cm) n-AFL featuring nano-sized grains via reactive sputtering. A thermal treatment at 1200°C was followed to ensure the structural integrity and stability. By optimizing sputtering power and oxygen partial pressure, we successfully suppress pore and crack formation and Ni agglomeration during the post-annealing, resulting in a durable AFL with enhanced performance characteristics.The optimized AFL, fabricated under 3kW sputtering power and 80% oxygen partial pressure, effectively mitigates structural defects induced by the thermal process. Consequently, TF-SOCs with n-AFL exhibit impressive performance in fuel cell mode, achieving power densities of 1286mW/cm2 at 650°C and 912mW/cm2 at 600°C. In contrast, cells without the n-AFL show low open-circuit voltages (OCV) of below 0.8V. It is speculated that the gas crossover is due to the pores generated from the heat treatment.

Tight Control of SiGe Condensation Technique for Large Scale Fabrication of High Quality Thick S0.5G0.5oi Layer

The development of thick pseudo-substrate of SiGe usually involves a complex epitaxy of several microns thick gradual buffer layer. However, a drawback of this approach relies on high roughness of the top layer which implies the addition of subsequent planarization step. Furthermore, if the top part of the layer is relaxed and defect free, abundant dislocations are embedded several microns deep. They can expand during following thermal processes, possibly reaching the surface. Obviously, these defects are detrimental for electronic and photonic purposes. State of the art studies report dislocations density around 106 cm-2 for on a Si0.7Ge0.3 substrate[1].This study shows an alternative approach based on the combination of the SiGe condensation technique combined with a thick epitaxy (figure 1). We demonstrate, using 300mm industrial conditions, that a tight control of SiGe condensation parameters (initial SiGe thickness and composition) allows to improve the structural quality of the thin SGOI to reach ultimate reduction of dislocations. Subsequently, this thin SGOI is used as a pedestal above which is grown a thick layer of SiGe using a simple, constant-composition epitaxy. The slippery SiGe/BOX interface is expected to relax part of the stress, allowing the growth of high quality thick SGOI layer [2,3].First, a thin epitaxy of 25nm fully strained Si0.8Ge0.2 is deposited by RP-CVD on a 300mm SOI wafer. The precursors gases are Germane, Dichlorosilane and Hydrochloric. Afterwards, SiGe condensation is performed using optimized high-temperature slow oxidation to generate thin SGOI structures, with Ge concentration varying from 40 to 55% [4]. Thickness and composition are characterized by Spectroscopic Ellipsometry. AFM and TEM cross-section allow the analysis of crystalline quality of both surface and core of the SGOI structures. The resulting thin SGOI structures exhibit typical defects at the surface revealing in-depth dislocations (figure 2). The defects density is around 105 cm-2 until 50% Ge concentration. Above this concentration, defects density increases rapidly toward 1010 cm-2, in agreement with literature [4,5]. Therefore, the next step focuses on thin SGOI with a maximum Ge concentration of 50%.When reducing the initial SiGe thickness and Ge concentration, defect density of the thin SGOI is strongly improved (figure 3). It exhibits a crucial impact of the stress contained in the initial SiGe layer. Especially, strong influence of the initial Ge concentration is observed: for a 20nm thick initial SiGe layer, a 0.5% decrease of the Ge concentration avoids any defect formation at the surface and in depth of the thin S0.5G0.5OI (figure 4). Raman measurement is performed on a S0.45G0.45OI structure and exhibits 1.6% in-plain strain, showing the pseudo-morphic behavior of the SiGe layer. This study shows that a precise control of the initial SiGe thickness and content allows to fabricate a dislocation free thin S0.5G0.5OI structure.Taking advantage of the weak SiGe/BOX interface achieving possibly stress relaxation, this SGOI structure is a promising compliant pedestal to limit defects creation during the subsequent thick Si0.5Ge0.5 epitaxy. A preliminary trial is achieved: above the defect-free thin S0.5G0.5OI structure, a thick SiGe epitaxy is grown using a constant Ge concentration during all the process. Ge concentration profile along the radius of the wafer was precisely tuned to match the one of thin SGOI (figure 5). The result is promising: no defects are observed in the top part of the layer, allowing a very smooth top surface and no noticeable interface is detected between the two SiGe layers, generating a homogenous crystal (figure 6). However, many crystalline defects are detected at the bottom of the SiGe layer. Analyzing several images, a defect density of 10⁹ cm⁻² is calculated. Though, a close look at the SiGe/BOX interface reveals the presence of SiO2 clusters, from which almost all defects are starting from. These clusters could be due to a bad surface preparation prior to the thick SiGe epitaxy, leaving Si-O or Ge-O residues that could migrate to nucleate into SiO2 precipitates. When growing, these precipitates create a stress field, helping defects formation. A somewhat similar issue was observed in literature [6]. A more efficient surface preparation is under development to completely remove these SiO2 clusters and drastically improve the final defects density.[1] Hartmann et al., Semicond. Sci. Technol., vol. 19, no 3, p. 311-318, 2004[2] Boureau et al., ECS, 2018[3] Usuda, et al., Solid-State Electronics, 2013[4] Valenducq et al., EUROSOI-ULIS, 2019[5] Takagi et al., ECS Trans., 33 (6) 501-509 (2010)[6] Kim et al., Opt Express. 2013 Aug 26;21(17):19615-23 Figure 1

Carbon-Based Materials As Negative Electrodes in Sodium-Ion Batteries

Nowadays effective energy storage, especially batteries, plays a crucial role in technology development. Due to the high abundance and low cost of sodium, sodium-ion batteries are promising substitutes for widely used Li-ion cells. Graphite-based materials are commonly used as a negative electrode in lithium systems. However, sodium ions have a larger ionic radius compared to lithium ones, and also the energy of intercalation of graphite by Na+ is higher than by Li+ [1]. Therefore, it is necessary to use different types of carbon- based materials with greater interlayer spacing, which can be achieved through increased structural disorder. These materials could be obtained through the thermal processing of polymers [2]. Additionally, due to their high porosity, the adsorption of sodium ions is more efficient. All these properties enhance the specific capacity of negative electrodes in sodium- ion systems.As a result of thermal processing, we obtained porous carbon-based materials. The synthesized powder's electrochemical characteristics have been examined using three-electrode Swagelok®-type cells. Slurry-coated electrodes with carbon-based materials were used as the working electrode, while sodium metal was used as the reference electrode and the counter electrode.Sodium-ion systems were investigated in a high-rate test, with a charging current of 1 C and discharge current rates varying from 1 C to 10 C. Even at the highest discharge current rate, the batteries retained a high percentage of the first-cycle specific capacity.The cycle stability of sodium-ion systems was also examined. After 50 cycles of charging/discharging at a current of 1 C, the specific capacity did not decrease significantly as compared to the specific capacity of the first cycle.Furthermore, the cyclic voltammetry behaviour of these systems was also investigated. Although the two signals were not well separated, it was evident that two electrochemical phenomena were present: diffusion of sodium cations in the carbon matrix and sodium adsorption on the carbon surface.The synthesised carbon-based porous materials demonstrated stability during the charging and discharging of sodium-ion batteries. The implementation of these products in sodium-ion technology could be helpful during the process of commercialization of such energy storage systems. Acknowledgements: This work was supported by The Polish National Centre of Science through a research grant 2021/43/D/ST5/01220 entitled “High-voltage sodium-ion batteries based on exfoliated graphite electrodes”.Literature:[1] Y. Liu et al. „Origin of low sodium capacity in graphite and generally weak substrate binding of Na and Mg among alkali and alkaline earth metals”, PNAS USA 113 2016 [2] T. Zhang et al. „Recent Advances in Carbon Anodes for Sodium-Ion Batteries”. Chem. Rec. 22 2022

Interface-Engineered Atomic Layer Deposition of Li4Ti5O12:Toward High-Capacity 3D Thin-Film Batteries

Atomic layer deposition (ALD) of lithium (Li)-based thin films has aroused significant interest in recent years. Promising applications are Li-ion thin-film batteries (TFBs), protective particle coatings, interface model systems, and neuromorphic computing [1,2]. Here, we demonstrate high footprint capacities and excellent high-rate performance of Li4Ti5O12 (LTO) fabricated by ALD for three-dimensional (3D) solid-state TFBs to power upcoming energy-autonomous sensor systems.The simultaneous increase of power and energy density of full-cell 3D TFBs by coating the battery layer stack over microstructured substrates was recently demonstrated [3]. The required conformal, pinhole-free deposition, and stoichiometric control of nanometer-thin films on highly structured surfaces are only accessible via ALD. The vapor-phase technique based on sequential, self-limiting surface reactions is well understood. However, the direct deposition of Li-based anodes remains challenging [1].In previous studies, we developed a thermal three-step ALD process for Li-containing mixed oxides on 200 mm silicon wafers [4, 5]. Lithium-tert-butoxide (LTB) and lithium hexamethyldisilazide (LiHMDS) were proven as suitable precursors, forming high-quality spinel LTO with low impurities after rapid thermal processing. The excellent electrochemical behavior of ALD LTO with LiHMDS was examined and linked to the film texture [5].In this work, we optimize the LTO ALD process with LTB towards high-capacity 3D TFBs and evaluate the electrochemical performance for the first time. A process with tetrakis (dimethylamino) titanium (TDMAT) and H2O at 300 °C was developed, leading to a saturated growth per cycle of 1.06 Å cycle-1 for 7 s LTB pulses. An ALD temperature window between 240 and 320 °C was identified. The effect of the substrate on the initial growth and crystallization behavior was investigated. To overcome the crystallization-inhibiting effect of the titanium nitride current collector, we introduced an ultrathin AlOx interlayer.Planar ALD LTO films with various thicknesses of up to 75 nm were manufactured, increasing the footprint capacity from 1.5 to 4.3 μAh cm-2. We observed a higher surface capacity contribution due to an increased roughness and an inferior C-rate performance with increasing film thickness. 50 nm LTO films demonstrate the optimum energy and power density. A footprint capacity of 1.95 μAh cm-2, corresponding to 67 % of the initial capacity, was achieved at 50 C with an average Coloumb efficiency of 99.9975 %.Next, we evaluate ALD LTO films as 3D TFB anodes for the first time. The conformality of the ALD process on microstructured substrates was improved by extending the LTB pulse and purge times. The purge time is the key factor enabling a step coverage of 70 % for holes with an aspect ratio of 10:1. The 3D samples with an area-enhancement factor (AEF) of 9 coated with 50 nm LTO obtained a footprint capacity of 20.2 μAh cm-2 at 1 C. The significant capacity enhancement of 6.9 compared to planar samples is according to the conformality. The remarkable high-power capability of 3D LTO is demonstrated with 7.75 μAh cm-2 at extreme currents of 5 mA cm-2. A capacity retention of 97.4 % after 500 cycles at 1 mA cm-2 shows the high-rate cyclability. The superior high-rate performance of ALD LTO compared to other 3D anode materials illustrates the enormous potential for realizing high-energy and high-power on-chip 3D TFBs.

All Inkjet-Printed Electronics from Electrochemically Exfoliated Two-Dimensional Nanomaterials

Inkjet printing is in the spotlight as a cost-effective and scalable method to assemble colloidal materials into desired patterns in a vacuum- and lithography-free manner. Two-dimensional (2D) nanosheets represent a promising class of nanomaterials for the fabrication of printed electronics due to their excellent adaptability to solution- based processing which facilitates the creation of stable ink formulations, accommodating a diverse array of electronic properties from metals, semiconductors, to insulators. Additionally, their dangling bond-free surface enables atomically thin, electronically-active thin films with van der Waals contacts which significantly reduce the junction resistance. This research presents a demonstration of fully inkjet- printed thin-film electronics consisting of electrochemically exfoliated graphene, MoS2, and HfO2 as metallic electrodes, a semiconducting channel, and a high-k dielectric layer, respectively. In particular, the high-k dielectric layer is prepared via two-step; electrochemical exfoliation of semiconducting HfS2 followed by thermal oxidation process to overcome incompatibility of electrochemical exfoliation with insulating crystals. Consequently, all inkjet-printed 2D nanosheets with various electronic types enable the fabrication of high-performance thin-film transistors, which exhibit enhanced field-effect mobilities and current on/off ratios of ~10 cm2 V-1s-1 and >105, respectively, at low operating voltage. Figure 1

Virus Detection Using Functionalized Graphene Oxide Composites

In this study, we explore the optimization of Reduced Graphene Oxide (RGO)-based sensors for detecting respiratory viruses, employing an innovative thermal reduction process. Traditional methods of graphene oxide (GO) production often struggle with scalability and uniformity. Addressing these challenges, we utilize a common glass substrate within a controlled oven environment, achieving precise temperature regulation essential for consistent sensor properties. RGO produced at these specific conditions demonstrated significantly enhanced uniformity and electrical properties when compared to those produced under traditional, less controlled conditions. Expanding upon this base, we have now incorporated metals (such as Fe, Ag) into the graphene oxide matrix to create metal-graphene oxide composites. These composites were methodically synthesized and integrated into our existing Field-Effect Transistor (FET) sensors, allowing us to evaluate their enhanced responsiveness to Human Parainfluenza Virus types 2 and 3 (HPIV-2, HPIV-3), and Respiratory Syncytial Virus (RSV). Early experiments with these new composites show a marked improvement in sensor sensitivity and specificity, particularly against HPIV-3, suggesting a robust interaction between the virus and the sensor interface. The addition of metal composites not only fortifies the electrical and mechanical properties of the sensors but also significantly boosts their viral detection capabilities. This advancement confirms the reproducibility and reliability of the optimized RGO production process, reinforcing the importance of precise thermal control in producing not just stable and uniform RGO, but also highly effective biosensing platforms. These results pave the way for the potential mass production of RGO-based sensors, equipped with metal-graphene oxide composites, targeting high sensitivity and specificity in virus detection. This enhancement has profound implications for the broad applicability of RGO in diverse fields including electronics, chemical sensing, and gas sensing, contributing foundational knowledge for the advancement of graphene-based technologies. This research reaffirms the critical need for standardized production processes that ensure the consistency and efficiency of RGO and showcases the practical application of these processes in creating high-performance biosensors.

Low Resistivity Metallic Films by Thermal Atomic Layer Deposition for High Aspect-Ratio Interconnects

Scaling interconnects to increase device density is a critical bottle neck for a range of applications from complementary metal oxide semiconductor (CMOS) to microelectromechanical (MEMS) switches and other devices. Currently, Cu is the interconnect metal of choice to fill vias but comes with significant challenges. To perform the fill, first a diffusion barrier is applied to ensure Cu leakage does not cause electrical breakdown between vias, then a metal seed layer is used to ensure smooth and dense Cu electroplating. Uniform seed resistivity, which can be correlated to thickness, is critical to produce low resistivity interconnects, free of voids. Unfortunately, state-of-the-art processes for high quality metallic films are limited to line-of-site techniques like chemical vapor deposition (CVD) or physical vapor deposition (PVD), limiting possible device pitch and architectures. When the aspect ratio increases above ~8:1 or there is a shadow, typically one of the layers is missing, resulting in insufficiently thin seed for successful Cu electroplating nucleation. This deficiency creates a void or produces a thickness gradient, resulting in pinch-off at the top. Ultimately, the device fails due to high line resistance or full dielectric breakdown. Fortunately, atomic layer deposition (ALD) can produce high density and low resistivity metal films for both Cu diffusion barrier and Cu electroplating seed applications. Here we report on a total solution to this problem using only thermal ALD. Adoption of ALD of metals has been slow in the market as traditional ALD reactors can be too slow and inefficient for production requirements or require plasma for sufficient film quality. Plasma enhanced ALD (PEALD) can produce quality films at a reasonable thermal budget, unfortunately every plasma process will have a limit to the aspect ratio that can be coated conformally and there is additional risk of surface plasma damage. Forge Nano has demonstrated single wafer thermal ALD technology to improve the speed and efficiency of ALD metal films, enabling a production worthy process. In this work a complete Cu barrier-seed stack solution has been demonstrated on Si vias ranging from 4:1 to 25:1 aspect ratio, showing successful Cu electroplating. A SiO2 ALD film, with a deposition rate of 10 nm/min, is first deposited to provide a dielectric barrier, then a thin TiN layer is applied as a Cu diffusion barrier, followed by a low resistivity Ru film for Cu adhesion. A novel TiN thermal ALD process at 300°C has been developed which decreases the as-deposited resistivity from ~1200 to <300 uΩ·cm at a deposition rate >1 nm/min. In addition, a high-quality Ru film has been developed with resistivity values <20 uΩ·cm and can be deposited on SiO2, HfO2, Pt, and TiN. An example of success as a total Cu barrier/seed stack for Cu electroplating in Si trenches is shown in Figure 1. When compared to PVD Ti/W barrier and Cu seed, the ALD stack produces dense, void free nucleation of Cu that remains well adhered to the via. However, the PVD stack has voids at the bottom of the trench from poor adhesion of electroplated Cu and narrowing at the top from a resistivity gradient within the trench, resulting in eventual pinch-off. From this comparison, it can be observed that the ALD Ru provides sufficient adhesion for Cu electroplating and that resistivity of the ALD Ru/TiN stack is sufficiently low and consistent for conformal and dense Cu electroplating. We expect this work to open up higher aspect ratio interconnects and possible new device architecture to the market. Figure 1

Effects of Ge and B Concentration in Selective Epitaxial Growth of Si1-XGex(:B) at Low-Temperature

As two-dimensional devices approach their scaling limits, monolithic complementary field-effect transistors have emerged to meet the demands of advanced transistors. A low thermal budget process is essential to prevent damage to the underlying layers while forming upper layers. Therefore, a low-temperature approach for the selective epitaxial growth (SEG) of SiGe(:B) in source-drain formation is necessary. The cyclic deposition and etch method was employed for its high selectivity, highlighting the need for further research into the incubation characteristics of B-doped SiGe. [1] We investigated the incubation behavior of SiGe(:B) on SiO2 under varying Ge and B concentrations in an ultra-high vacuum-chemical vapor deposition (UHV-CVD) chamber. In this study, we investigated the influence of the Ge and B concentrations on the incubation time for SiGe(:B) on SiO2, comparing it with the epitaxial growth on Si(100) and Si(111). First, we analyzed the incubation properties of undoped Si1-xGex (0 < x < 0.4) layers. We then explored the effect of B concentration by varying the B flow rate. Our findings indicate the higher Ge concentrations extend the incubation time, independent of the total gas flow rate. In contrast, B doping reduces the incubation time compared to with that of undoped SiGe, and increasing B concentration further shortens the incubation time. Atomic force microscopy and scanning electron microscopy were used to examine amorphous formation on SiO2. In addition, high-resolution X-ray diffractometry and ellipsometry were used to analyze Ge and B concentrations, as well as growth thickness. Our study offers comprehensive insights into the low- temperature SEG process window for SiGe(:B). Acknowledgment This work was supported by the Technology Innovation Programs (RS-2023-00235609) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea).

Insight into the Thermal Washing Mechanism of Sodium Lignosulfonate Alkyl/Sodium Persulfate Compound on Oily Sludge.

The thermal washing of oily sludge using sodium persulfate (SD) assisted by sodium lignosulfonate surfactant has been demonstrated to be an effective method for oily sludge remediation. To further explore the underlying mechanisms of this process, a systematic study was conducted by simulating oily sludge systems consisting of saturated hydrocarbons (SaH), aromatics hydrocarbons (ArH), resins (Res), and asphaltenes (Asp). The effects of reaction conditions, such as pH, sodium lignosulfonate alkyl (LSA) concentration, SD concentration, and washing temperature, were analyzed. Furthermore, the oxidative kinetic mechanism during the reaction process was investigated. The results demonstrated that neither petroleum hydrocarbons nor SD underwent significant chemical transformations when exposed to LSA, while SD exhibited a marked oxidative degradation effect on all four types of hydrocarbons. Oxidation kinetics indicated that sodium hydroxide played a catalytic role, with SD being the main oxidant and particularly efficient in degrading Asp and Res. Meanwhile, LSA contributed to the removal of hydrocarbons by reducing the surface tension of the solution, enhancing solubilization. This study not only elucidates the central role of SD in the thermal washing process but also provides a solid theoretical foundation for the practical application of this technology in oily sludge treatment.

Cell Design and Optimization for Efficient Hydrogen Production through Ammonia Electrolysis

Hydrogen, pivotal for a carbon-neutral energy framework, faces hurdles in storage and transport, leading to the consideration of ammonia as a viable hydrogen carrier. Compared to hydrogen, ammonia can be liquefied at moderate temperatures and has higher energy volumetric density. Despite ammonia's potential, presently an energy-intense thermal cracking process is necessary to convert it back to hydrogen. This prompted us to explore ammonia electrolysis as a less energy intense, more sustainable alternative for ammonia-to-hydrogen process. This method promises lower theoretical energy consumption and could in principle be driven by renewable energy sources. The number of research efforts focusing on ammonia electrolysis (ammonia electro-oxidation) is limited and most frequently focuses on catalyst development to minimize poisoning and overpotentials. Studies pursuing electrolysis cell designs for ammonia oxidation are even scarcer. Our study delves into design strategies for an ammonia electrolyzer, pairing ammonia oxidation with hydrogen evolution, aiming to optimize the entire process to enhance the prospects of ammonia as a hydrogen carrier.This presentation will compare three different designs for ammonia electrolysis: batch, flow, and membrane electrolyte assembly (MEA) cell configurations. Each cell is characterized with respect to durability and product selectivity. Ultimately, we studied multiple factors, including flow rate, ammonia concentration, pH, and different operation protocols for MEA cells. The results provide guidance toward optimal cell design and operational protocols for a high-performing ammonia electrolyzer.

Redox Behavior of Quinones Bearing Ionic Liquid Moiety for Electrochemical CO2 Capture

CCUS (Carbon dioxide Capture, Utilization and Storage), is attracting attention as an effective method for reducing carbon dioxide (CO2) emissions toward carbon neutrality by 2050. Currently, chemical absorption followed by thermal desorption using liquid amine is employed as the CO2 capture and concentration technology. However, low energy efficiency and high cost of the thermal swing process remain to be addressed. CO2 capture driven by renewable electricity represents a promising alternative approach to mitigate CO2 emissions and address climate change. Electrochemically mediated carbon capture can be achieved by developing redox-active CO2 adsorbents, such as quinones. In aprotic electrolytes, reduced quinone species can selectively uptake CO2 from a dilute feed upon electro-reduction via a nucleophilic addition reaction and release a concentrated CO2 upon electrochemical oxidation. However, the low solubility of quinones in nonaqueous solvents limits their total CO2 carrying capacity in the system. We synthesized a salt of imidazolium modified anthraquinone with ionic liquid-like structure to address the solubility issue. The synthesized cationic quinone derivatives showed more than 100 times higher solubility and high ionic conductivity as well as electrochemically reversible CO2 adsorption-desorption. In addition, we synthesized anionic quinone derivatives, anthraquinone with sulfonate (SO3 −) moiety, by one-step salt metathesis reaction, and confirmed that the negatively charged quinones is also applicable to the electrochemical CO2 capture. We report the electrochemical CO2 capture-release behaviors of the ionic quinones and its monitoring using in situ spectroscopic analysis with the aid of density functional theory calculations.Reference:Iida, S. Kondou, S. Tsuzuki, M. Tashiro, N. Shida, K. Motokura, K. Dokko, M. Watanabe, K. Ueno, J. Phys. Chem. C, 2023, 127, 10077.

(Invited) Interface Control Process of Rare-Earth Oxides on Si for Gate Dielectric Application

High-k gate dielectrics are indispensable to overcome the shot-channel effect in scaled CMOS devices [1]. Besides the enhanced electrostatic control of the gate electrode, high-k/Si interface properties, including interface state density, fixed charges, dipoles, carrier mobility, reliability, and so on, need to meet the requirement levels. Rare earth oxides have been intensively studied for gate dielectric applications as these oxides react with Si to form a silicate layer, whereas, for the HfO2 case, a SiO2-based low-k interface layer is formed. One of the issues for rare earth oxide gate dielectrics is controlling the reaction amount while obtaining a good interface property. In this presentation, the interface reaction of rare-earth oxides and Si is modeled and controlled by the thermal treatment process. Furthermore, the influence of the metal gate electrode on the interface is assessed. A la-silicate interface layer is formed between the La2O3 film and Si interface. Although the La atom content in the reactively formed silicate layer generally depends on the annealing environment, a silicate/Si interface can be easily formed, which is advantageous for gate dielectric scaling. However, even under the same process, the La atom content in the silicate increases with the thinning of the initial La2O3 thickness, and the interface state density, flat-band voltage, and mobility degrade [2]. The reaction between La2O3 and Si can be modeled by oxygen atom supply from the environment, and the influence of the metal gate can explain the degradation of electrical properties. A La-rich silicate can be formed with nice interface properties by controlling the supplied oxygen atoms by selecting a proper metal gate stack [3]. The crystal grain size in the metal gate also affects the interface state density. A low interface state density can be obtained by adopting a metal gate material with nano-sized grains [4].In conclusion, an interface control process of La2O3 film on Si is presented by limiting the oxygen atom supply during the interface reaction. La-rich silicate, a high-k film, can be obtained by adopting a proper stacked gate structure. Also, nano-sized grains in the metal electrodes can exhibit a decent interface property.[1] J. Robertson, et al., Materials Science and Engineering R, 88, 1 (2015).[2] K. Kakushima, et al., Solid-State Electron., 54, 715 (2010).[3] T. Kawanago, et al., IEEE Trans. on ED, 59, 269 (2011).[4] K. Tuokedaerhan, et al., Appl. Phys. Lett., 104, 021601 (2014).

A novel process for recovery of vanadium and chromium from vanadium-chromium sludge: Roasting pretreatment and thermal reduction co-alloying process

Vanadium (V) and chromium (Cr) are significant strategic metals and has been widely used in many applications. In order to realize resource utilization and harmless disposal of this metallurgical solid waste, an effective and clean process was proposed in this paper to recover V and Cr from this wastewater purification sludge (WPS), namely roasting pretreatment and thermal reduction co-alloying process. After a roasting pretreatment at 1000 °C, water and more than 75% of sulfur in sludge were removed from the WPS. The pre-treated sludge was used to produce Fe-Cr-V alloy by carbon thermal reduction co-alloying method with Fe2O3 powders as an additive. The thermodynamics software Fact Sage 8.3 was utilized to assess the feasibility of the reduction reaction and to design the components of both the slag and the alloy. The recovery rate of V and Cr were 99.4% and 99.6%, respectively, under the conditions of theoretical reducing agent dosage (W=nC/nO) value of 1.0, binary alkalinity (R = wCaO/wSiO2) value of 1.06, and the temperature of 1550 °C. In addition, the mass percentages of Fe, Cr, and V in the left slag were 0.38%, 1.07%, and 0.09% (in Fe2O3, Cr2O3 and V2O5), respectively, which was tested to be non-hazardous waste. This work opens up a clean and efficient way of recovering valuable Cr and V from metallurgical solid wastes.

Durable Ion-Pair High-Temperature Proton Exchange Membrane Fuel Cells with a Low Platinum Loading Intermetallic Catalyst

Conventional high-temperature proton exchange membrane fuel cells (HT-PEMFCs) often necessitate a relatively high platinum cathode loading, primarily due to the undesirable issue of phosphate poisoning. Previous research has suggested that employing ordered Pt-alloy catalysts could mitigate this problem [1, 2]. Our study demonstrates that an ion-pair proton exchange membrane (PEM) based on quaternary ammonium functionalized membrane can further alleviate phosphate poisoning by reducing the concentration of phosphoric acid in the electrode [3, 4].In this study, we integrate two strategies: the utilization of intermetallic catalysts and the ion-pair PEM platform, aiming to decrease the Pt loading of the catalyst without compromising performance and durability. Carbon-supported intermetallic PtCoNiCrN catalysts were synthesized via a single thermal annealing process [5, 6]. Their crystallographic structure was confirmed through X-ray diffraction, atomic-resolution transmission electron microscopy, and in-/ex-situ X-ray absorption spectroscopy.Rotating disk electrode (RDE) experiments revealed that the half-wave potential of ORR of the intermetallic PtCoNiCrN/C in 0.1 M H3PO4 with 0.1 M HClO4 was 876 mV, surpassing that of disordered PtCoNiCrN/C (829 mV) and commercial Pt/C (TEC10E20E) catalysts (769 mV). In membrane electrode assembly (MEA), the MEA utilizing the intermetallic catalyst with a platinum loading of 0.3 mg cm-2 exhibited a current density of 0.212 A cm-2 at 0.7 V and the peak power density (PPD) of 713 mW cm-2 under H2/air conditions, significantly outperforming the MEA employing the commercial Pt/C catalyst with optimized electrode composition (0.103 A cm-2 at 0.7 V and PPD of 625 mW cm-2).Remarkably, the intermetallic catalyst demonstrated stable operation for 1,000 hours at 160 °C under anhydrous conditions without notable performance degradation. This study presents a pathway to reduce the catalyst loading of HT-PEMFCs, emphasizing the crucial role of the crystallographic structure of nanoparticles in enhancing the performance of HT-PEMFCs. Acknowledgments This work was supported by the US Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office (L’Innovator program).

An Extendible Multiphysics Model of a Single Water Electrolysis Cell

The important role that renewable hydrogen has in the energy transition is undeniable given the capability of decarbonizing sectors difficult to electrify acting as the link between electrical energy from renewable sources and molecules for future energy systems. Therefore, improvement of the efficiency, cost and durability of electrolyzer systems is key. The discovery of new materials is one of the research areas in which a lot of effort is focused given that finding more electrochemically active materials allows to reduce overvoltages improving the electrical performance of the electrolyzers. The requirement for these materials is also that they are durable under operating conditions and cheap to produce in order to achieve improvements in all relevant aspects of the technology.In water electrolysis systems, kinetics, heat management, gas quality, among others, are relevant aspects to understand in order to achieve performance gains. In this line, computational modeling plays an important role in analyzing and understanding the performance of such systems, as well as the effect that different variables have on it. Given the nature of the water electrolysis process, a multiphysics approach is necessary to account for electrochemical, mass transfer, thermal and fluidic processes, as well as their interactions.Computational models and digital twins are gaining great momentum in electrolysis systems applications, but its availability is limited as its development requires of deep physical knowledge of the different phenomena and their interactions, or large amounts of data. When data is available data-driven models are very useful but the results are not easy to extrapolate when a change in design or materials happens. Therefore, physics-based modelling is a useful tool, as characterization at small scale and short-term is the first step in the discovery of new materials, which allows to obtain physical parameters that act as input for the computational model. This way it is clear that the advantage of developing a physical model is that the model becomes generic, which means that by changing the corresponding design parameters, the performance of a different design can be analyzed.The current project aims to develop an extendible physics-based model of a single water electrolysis cell. This development will allow to modify different parameters or operating conditions of the cell design and analyze the effect of those changes in the performance. Additionally, the extendible nature allows for its use as single element for analyses in 1D if desired.The model, developed in OpenModelica, is capable of reproducing the polarization curve of an electrolysis cell, the temperature change between inlet and outlet, the gas crossover and the pressure loss.

Electrochemical Pump for Hydrogen Separation and Purification from Exhausted Gas Mixture

The hydrogen economy is a vital strategy for mitigating climate change and energy security through the establishment of an environmentally sustainable energy framework. To use hydrogen as a stable fuel, high purity is essential. Hydrogen separation technology can be classified into two types: Pressure Swing Adsorption (PSA) and Electrochemical Hydrogen Pump (ECHP). PSA operates by adjusting the pressure to release the adsorbed gas. It has disadvantages such as complexity, large footprint and high energy consumption. The electrochemical hydrogen pump is a technology that can overcome these disadvantages. Electrochemical hydrogen pump consists of electrode, gas diffusion layer, catalyst, and proton exchange membrane. Among these components, the catalyst is a direct factor affecting the performance and durability. Pt, mainly used as a catalyst, is known to have excellent performance in the HOR and HER. However, it suffers from CO2 poisoning, which causes performance degradation. As the requirement of hydrogen separation in gas mixture has increased, the need for a catalyst that can maintain performance under exhausted gas mixture. This study manufactures Iridium-based catalyst electrodes with strong resistance to CO2 poisoning. We deposit an Iridium oxide layer onto Carbon paper using an electrochemical deposition method, enabling the formation of thin and uniform catalyst layers by adjusting the voltage and time. Through a thermal reduction process, we form a metallic Iridium layer on the surface. The application of electrode with thin and uniform Ir/IrOx catalyst layer to lab-scale ECHP is expected to improve long-term performance.

Controlled Surface Polarity and Crystallinity of Gallium Nitride on Si (111) Using Atomic Layer Deposition for Selective Wet-Etch and STEM Analysis

Gallium nitride (GaN) has gained interest as photoelectronic materials and a buffer layer for other III-V deposition with applications in power electronics operated at high voltage and high temperature. The crystallinity and polarity of III-V semiconductors have a key role for the passivation layers on microLED, the formation of 2D electron gasses in high electron mobility transistors, and for templating growth of piezoelectric materials. The atomic layer annealing (ALA) was reported to improve the crystallinity of the III-V compounds (aluminum nitride) at low temperatures as compared to the conventional thermal ALD. In ALA, a pulse of ion bombardment is added to each ALD cycle to ensure polycrystalline film formation at low temperature. Polycrystalline GaN has been deposited by ALA at low temperatures even on amorphous substrates, but the polarity was not reported. The selective wet-etch process has several advantages for the III-V semiconductor device integration since the conventional plasma ion etching process is expensive, complicated, and leads to the surface damage by reactive plasma ion. The GaN surface polarity (N-polar or metal-polar) on sapphire was selectively etched by aqueous KOH solution. However, electrochemical etching study on the polarity of GaN ALD films has not yet been studied as types of ALD process. Figure 1a and 1b show the process parameter switching diagram for the GaN thermal ALD and GaN ALA processes, respectively. The chemical compositions of ALA and ALD GaN on Si were estimated by in-situ AES as shown in Figure 1c. Lower O content (below 3.3 at. %) and higher N/Ga atomic ratio were observed in the ALA GaN on Si (111) as compared to the thermal ALD GaN film (4.6 at. %). Figure 1d shows that the intensity of GaN (002) XRD pattern in thermal ALD GaN on Si was greatly improved in the GaN stacks (GaN thermal ALD/ALA/Si) with an ALA GaN buffer layer. The electrochemical behavior of the GaN ALD films was studied to elucidate the impact of surface polarity on selective KOH wet-etch. The linear sweep voltammograms of GaN thermal ALD and GaN ALA films in 1 M KOH solution were shown in Figure 1e. The applied potential was swept from zero (vs. Normal Hydrogen Electrode) to positive 3.7 V. The peak of current density at ~1.7 V was observed in the voltammogram of the GaN ALA film (N-polar), suggesting the occurrence of etching reaction by the dissolution and formation via the equations in Figure 1f. On the other hand, the absence of current density peak in the GaN thermal ALD film (Ga-polar) could suggest the unfavorable etching reaction as compared to the GaN ALA film. Figure 2a and 2b shows the HAADF-STEM images of ALD GaN on Si demonstrate highly ordered 3 nm x 5 nm ALD GaN layers with bright and dark regions. The circles of bright regions and the center of dark regions represent Ga atoms and tunnel points (empty element), respectively. The GaN polarity could be determined by drawing triangles connecting adjacent three tunnel points without the interruption of Ga. Using this method, upward triangles were obtained in the HAADF-STEM image (Figure 2a), suggesting the formation of N-polar GaN layers during the ALA GaN process on Si. Conversely, downward triangles from the STEM image of thermal ALD GaN /ALA GaN /Si (Figure 2b) suggested Ga-polar GaN during GaN thermal ALD process. The inset figures show the top-view SEM image of selectively wet-etched (30 min, 20 wt.% KOH (aq)) GaN films. The etched surface on the ALA GaN layers (inset of Figure 2a) indicated N-polar GaN surface. The inset SEM image in Figure 2b shows a nearly unchanged GaN surface in thermal ALD GaN /ALA GaN / Si is consistent with the Ga-polar GaN surface. These observations are in good agreement with the HAADF-STEM images.The data is consistent with being able to control the polarity of GaN by switching between thermal ALD and ALA. The ion bombardment in ALA promotes N-polar GaN while thermal ALD promotes metal polar GaN. This allows the facile formation of both electron and hole gas layers between ALA and ALD GaN. Figure 1

Modeling and Optimization of Wet ALE Process

Atomic layer etching (ALE) has become an important process for semiconductor device manufacturing due to its unique ability to control surface etching with single molecular level control. ALE first began in the laboratory over thirty years ago, and in the past ten years it has matured into an important part of the semiconductor manufacturing process with several solutions available on the market for high volume manufacturing.Most ALE processes have been developed in a vapor or rarified gas environment, often using a thermal or plasma process to facilitate the required chemical reactions. (1) In recent years there has also been work on digital etching with liquid chemistry, including ALE processes for copper, cobalt, ruthenium, and noble metals (2-5).With wet ALE processes relatively unexplored compared to the longer studied vapor phase processes, there has not been much work done to understand how the interaction of fluid flow and the chemical reaction kinetics can affect a wet ALE process. Digital wet etch processes generally require two different solvents for the ligand deposition/adsorption and subsequent etching steps, and it’s important to minimize any mixing of the two liquids: otherwise the etch process ceases to be digital and instead becomes a continuous etch process, with resulting problems in roughness and local nonuniformity.In this paper we will present results of a series of simulations to model the sequentially switching liquid flow and surface reactions of an ALE process: both in a simplified flow cell system and in center dispense over a spinning wafer.The ALE reactions are modeled assuming Langmuir isotherms: one for the ligand deposition and another for the subsequent etching step. The kinetic equation for a pseudo first order heterogeneous surface adsorption isotherm is as follows: dq/dt = k(qe - q)Where q is the surface adsorption density, t is time, k is the reaction rate constant, and qe is the equilibrium concentration of the adsorbate. qe is determined using the standard Langmuir isotherm: qe = q∞ (K cA /(1 + K cA ))Where q∞ is the maximum possible surface adsorbate concentration, cA is the concentration of adsorbate in the solvent, and K is the Langmuir adsorption equilibrium constant. A similar set of equations are used for the desorption in the etching step, with different values for the rate constant k and equilibrium surface density qe .An example of the spinning wafer liquid dispense simulation is shown in Figure 1. This is an axisymmetric simulation, where liquid is being continually dispensed at 1 L/min onto the center of a wafer spinning at 1000 RPM, with the liquid switching to a different solvent at t = 0. The figure shows the volume fraction in the liquid film at 0.1s as the displacing fluid flows from the center of the wafer at the left to the edge of the wafer at the right. The volume fraction at the bottom boundary, which represents the wafer surface, shows that the transition from one solvent to another is not instantaneous, and that there will be some mixing between the two.Our analysis and results will also include dimensional analysis of the chemical reaction and fluid flow system, showing how parameters like reaction rate constants, spin speed, dispense flow rate, flow velocity, and solvent switching frequency can affect the etching performance in terms of etching uniformity and surface roughness for any generalized wet digital etch system. Kanarik, K. J.; Lill, T.; Hudson, E. A.; Sriraman, S.; Tan, S.; Marks, J.; Vahedi, V.; Gottscho, R. A. Overview of Atomic Layer Etching in the Semiconductor Industry. JVST A 2015, 33 (2), 020802.Netzband, C.; Arkalgud, S.; Abel, P.; Faguet, J. Wet Atomic Layer Etching of Copper Structures for Highly Scaled Copper Hybrid Bonding and Fully Aligned Vias. In 2022 IEEE 72nd Electronic Components and Technology Conference (ECTC); 2022; pp 707–711.Abel, P. Wet Atomic Layer Etching Using Self-Limiting and Solubility-Limited Reactions. US10982335B2, April 20, 2021.Abel, P. Methods for Wet Atomic Layer Etching of Ruthenium. US11802342B2, October 31, 2023.Abel, P. Methods for Wet Etching of Noble Metals. US20230121246A1, April 20, 2023. Figure 1

Preparation of Solid Electrolytes Containing Highly Concentrated Electrolytes and Effects of Solidifying on Physicochemical Properties

Currently, safety improvements for the electrolyte of conventional lithium-ion batteries is desired owing to their apprehending accidents of firing by contained flammable organic solvents. Safety ensuring is a very important issue for the expansion of larger sizes and applications. Recently, highly concentrated electrolytes containing an extremely high concentration of electrolyte salts are drawing attention as a new electrolyte design. The highly concentrated electrolytes reported unique characteristics such as greatly improved thermal stability and expanded electrochemical window(1). However, the solvation structure of highly concentrated electrolytes remains unclear. In this study, we proposed gel polymer electrolytes (GPEs) composed of highly concentrated liquid electrolytes using chemically cross-linked polyether-based polymers. We investigated the physicochemical properties and battery characteristics of GPEs. The aim of this study is to develop an electrolyte design that improved the safety and performance of rechargeable batteries.In this study, all GPEs were prepared in an Ar-filled glovebox. LiFSA+xEC (0.8≦x≦4) liquid electrolytes (LE) were prepared by mixing EC and LiFSA, and GPEs were also prepared by LiFSA+xEC (0.8≦x≦4), polyether-based polymers (P(EO/PO = 0.8/0.2)) and DMPA as a photoinitiator, and irradiated UV for 5 min. Prepared GPEs samples were evaluated for thermal properties, ionic conductivity, and solvation structure by thermogravimetry (TG), The self-diffusion coefficients (D) and Raman spectrometric method, respectively.To analyze the solvation structure of Li+ in the highly concentrated electrolytes, Raman spectra were measured in the wavenumber range of 680-860 cm−1. Figure 1 shows the obtained Raman spectra of prepared GPEs. The observed peak was attributed to the symmetric stretching mode of FSA- anion and confirmed shift to high wavenumber with LiFSA concentration. The peak shift of FSA- was suggested for the formation of aggregate structures by change of dissociation properties to contact ion pair (bound FSA-) from separated solvent ion pair (free FSA-).Figure 2 shows the TG curves of each GPEs. TG data was obtained the heating scan rate of 10 K min-1 from 303 K to 753 K. The thermal stability of GPEs improved with LiFSA concentrations. GPEs of high Li salt concentration were suggested the formation of aggregate structure, and the strong interaction between Li+- ethylene carbonate, formed a quite strong solvation structure. In general, the aggregate structure is caused by strong interaction between lithium cation and ethylene carbonate. Also, LiFSA+xEC electrolyte solution exhibited decreasing tendency of free EC and improvement of thermal stability(2). From the above results, a change of solvation structure in GPEs was suggested to improve thermal stability. Although LiFSA+xEC electrolytes showed multiple steps of thermal weight loss processes, prepared GPEs exhibited that in one step. Therefore, proposed component materials of GPEs achieved sufficient homogeneously without phase separation and lower thermodynamic activity of the solvent.The ionic conductivity(σ) of prepared GPEs was evaluated by alternating current(AC) impedance measurements using hermetically sealed cells. AC impedance measurements were conducted by cooling from 333 K to 263 K at 10 K intervals. The temperature dependence of the σ for the electrolyte using Arrhenius-type plots is shown in Figure 3. σ decreased with LiFSA concentration. σ also increased with temperature following with VFT equation. Also, LiFSA+xEC electrolyte solution exhibited tendency of the viscosity increased with LiFSA concentration(2). From the above results, decreased of σ with increasing concentration was due to increase viscosity.The self-diffusion coefficients (D) were measured by PFG-NMR with a superconducting magnet and equipped with a pulsed-field gradient multiprobe. Figure 4 shows the self-diffusion coefficients (D GPE and D LE) of ions and EC were measured between 333 K and 303 K to evaluate the diffusion behaviors in the electrolytes of x = 4.0.The order of D is D EC > D FSA > D Li for the diluted electrolyte of x = 4.0 and increasing D GPE with temperature. D GPE decreased with solidification compared to D LE. Figure 5 also shows the D GPE of ions and EC were measured between 333 K and 303 K to evaluate the diffusion behaviors in the electrolytes of x = 0.8. D Li increased compared to the electrolytes of x=4 relatively. Also, the order of D is D Li > D EC > D FSA in highly concentrated electrolytes at 333 K.The calculated t Li of the electrolyte at 333 K is shown in Figure 6. The t Li increases with the increased LiFSA concentration. The highest t Li was obtained when x = 0.80. The significant increase in the t Li at high LiFSA concentrations reflects faster diffusion of Li+ compared with anions.[1] Y. Yamada, A. Yamada, J. Electrochem. Soc., 162(14), A2406-A2423 (2015).[2] R. Furui, et.al, J. Phys. Chem. C, 127, 10748-10756 (2023). Figure 1

Mitigating Gas Evolution in Electron Beam-Induced Gel Polymer Electrolytes through Bi-Functional Cross-Linkable Additives

Currently, high-capacity LIBs commonly employ LiPF6-based liquid electrolytes (LEs) and high-nickel (Ni) layered oxide cathodes, such as Li[NixMnyCo1-x-y]O2 (NCM, x > 0.7). Although the LEs provide superior ionic conductivity, their intrinsic flammability and potential for leakage pose significant safety challenges. In addition, the generation of acidic species (e.g., POF3, PF5, and HF) from LiPF6 salt decomposition exacerbates the degradation of solid-electrolyte-interphase (SEI) and cathode-electrolyte-interface (CEI) layers. The high-Ni NCMs are particularly vulnerable to structural degradation and accelerate side reactions with the LEs under elevated voltages and temperatures, generating considerable gaseous byproducts, which, in turn, significantly increase the risk of battery explosion. Instead of LEs, solid-state electrolytes are considered safer alternatives owing to their enhanced safety. Yet, they have encountered obstacles such as unstable interface, low ionic conductivity, and the need for high processing temperatures exceeding 1000 °C. Therefore, designing a suitable electrolyte that simultaneously provides both safety and excellent interfacial compatibility is paramount.One of the emerging solutions is in-situ gel polymer electrolytes (GPEs), developed by incorporating a liquid precursor into the cell followed by polymerization, thus ensuring commendable electrode compatibility. Commonly, the production of in-situ GPEs employs a thermal curing process. However, its demand for an initiator, elevated temperatures exceeding 50 °C, and prolonged polymerization time can negatively impact battery components. Conversely, high-energy electron beam (E-beam) irradiation can initiate polymerization uniformly and rapidly within a minute without an initiator. Further, it can penetrate deeply into thick materials, even aluminum (Al)-based packaging of pouch-type batteries, making it an advantageous technique for widespread battery applications and conducive to mass production.In our research, we have developed a safe and commercially viable E-beam-induced GPE (E-Gel) with enhanced interfacial compatibility and minimal gas-related hazards using bi-functional cross-linkable additives (CIA). Dipentaerythritol hexaacrylate (DPH) is selected as a CIA for its proficiency in forming E-Gel with sufficient mechanical strength and Li-ion conductivity, achieving up to 80% of LEs with minimal addition of 3%.Key aspects of our work are as following. 1. Innovative GPE fabrication process Our work diverges fundamentally from existing methodologies by leveraging the bi-functional capability of DPH in a two-stage process involving initial electrochemical activation followed by E-beam-induced polymerization. Unlike conventional methods where a liquid precursor solution containing a monomer is injected and cured immediately after cell assembly, our process involves assembling a cell with a precursor solution and initiating the polymerization through electron beam irradiation after the first charge and discharge cycle. This sequence allows DPH to function as an additive during the initial cycle, establishing stable and robust polymeric SEI and CEI and as a crosslinker during the E-beam irradiation step, forming a polymer framework. Consequently,the DPH-derived SEI and CEI layers obtained by utilizing DPH as an additive had lower Young’s modulus values of 110.0 and 42 MPa, respectively, than the LE-derived SEI (289.2 MPa) and CEI (111.5 MPa). These findings suggest that the polymeric DPH-modified SEI and CEI layers possess soft and flexible attributes, enabling them to endure mechanical deformation during the Li-ion insertion-extraction processes occurring within the layered Gr and NCM811 materials. Enhanced interfacial compatibility at the electrode/E-Gel interfaces DPH first forms a stable, polymeric interface layer which acts as a protective shield for the electrodes during the first cycle. Then, during the E-beam irradiation step, the C=C bonds in the decomposition products of DPH on the electrode surface can be co-crosslinked with the acrylates within the residual DPH monomer. In other words, the polymer matrix within the GPE is integrated with cathode and anode surfaces, thereby augmenting the E-Gel's structural integrity and interfacial compatibility. Such an integrated system establishes continuous ion transport pathways at the GPE/electrode interphases, promoting ion conductivity and facilitating Li-ion migration. Improved safety and performance in practical applications Our research demonstrates that the E-Gel significantly reduces the release of hazardous gases by 2.5 times compared to LE, particularly during the initial formation stage. This is because the preferential decomposition of DPH to form stable SEI/CEI effectively alleviates the breakdown of EC. Outstandingly, the 1.2 Ah pouch cell incorporating E-Gel maintains a high capacity of 1.0 Ah after 200 cycles at 55 °C while preserving good contact between the electrodes with low gas generation.In summary, our research introduces a novel approach to the fabrication and application of gel polymer electrolytes for LIBs, leveraging the unique properties of DPH and a strategic E-beam irradiation process. Figure 1