High Electrochemical Stability Research Articles

Mitigating Zinc Dendrite Formation and Parasitic Side Reactions in Aqueous Zn-Ion Batteries Via Laser-Assisted Carbonization of Cu-PANI Films on Zn Anodes.

Aqueous zinc-ion batteries (ZIBs) are gaining attraction for large-scale energy storage systems due to their high safety, significant capacity, cost-effectiveness, and environmental friendliness. On the other hand, the development of aqueous ZIBs is restricted by the limited practical application of zinc (Zn) because of the high reactivity of Zn in aqueous electrolytes, which results in the severe dendrite growth and parasitic side reactions such as hydrogen evolution reaction (HER). In this study, heteroatom-doped carbon porous surface modification by laser-assisted carbonization of copper (Cu) doped polyaniline (PANI) is designed and fabricated on top of the Zn metal anode (c-Cu-PANI/Zn). The c-Cu-PANI surface-modified Zn anodes exhibit high electrochemical stability and performance during the Zn plating-stripping cycles and suppress the dendrite formation. The symmetrical cell and half-cell with the c-Cu-PANI/Zn anodes exhibit stable cycles for 6000h and 100% Coulombic efficiency for 2500 cycles, respectively. Moreover, the c-Cu-PANI/Zn║V2O5 cell delivers a high specific capacity of 319 mAh g-1 at 0.2 A g-1, which is significantly higher than that of the bare Zn║V2O5 cell (240 mAh g-1). It is believed that applying c-Cu-PANI as a surface modification can enhance the stability and reversibility of the Zn anodes, therefore accelerating the commercialization of ZIBs.

Effect of Fluorine Segments in Fluoropolymer Matrix on the Properties of Gel Polymer Electrolytes

AbstractPolymer quasi‐solid electrolytes have been paid widely attention in account of their outstanding advantages in safety, flexibility, viscoelasticity and film formation. Fluoropolymer is used as matrix of gel electrolytes not only has high electrochemical stability, but also facilitates the dissociation of lithium salts owning to the strong electron‐absorbing C−F groups, which makes it a very promising choice for the further development of gel electrolytes. Due to the different sites of C−F bonds, their activity is also diverse, which results in the difference of the mobility of lithium ions and the LiF composition of SEI film on the surface of lithium metal anode. As a result, distinct fluorine‐containing gel polymer electrolytes are prepared by in‐situ polymerization of two different monomers, HFMA and TFMA. Compared with −CF3 on terminal group in TFMA, the gel electrolyte polymerized with HFMA whose C−F group with stronger electronegativity is at the intermediate carbon site, as polymer matrix has better performance. The ionic conductivity achieves 7.02×10−3 S cm−1 at room temperature, and the assembled batteries have a capacity retention rate of 91 % after 200 cycles of 1 C. Our research has laid a solid theoretical foundation for the further development of quasi‐solid electrolyte.

Implementation of phosphonium salt for high-performance supercapacitors from room to ultra-low temperature conditions

Conventional supercapacitors encounter limitations in operating voltage and performance at low temperatures due to poor ionic conductivity and diminished interfacial dynamics in electrolytes. In this study, we synthesized the phosphonium salt 5-phosphinaspiro[4.4] nonane tetrafluoroborate (PSNBF4) for the first time. We extensively characterized the physical and electrochemical properties of PSNBF4 in acetonitrile (AN) and propionitrile (PN) as electrolytes, assessing their performance in supercapacitors at room temperature and − 40 °C. The results demonstrate PSNBF4 electrolytes exhibit high solubility, outstanding ionic conductivity (1 M PSNBF4/AN: 49.8 mS cm−1; 1 M PSNBF4/PN: 27.5 mS cm−1), and high electrochemical stability, contributing to good capacitance retention after 500 h of floating tests at 25 °C. Supercapacitors using PSNBF4/AN retained 78 % of their capacitance at 3.1 V, whereas those with PSNBF4/PN maintained 68 % at 3.2 V. Impressively, these supercapacitors performed exceptionally well at −40 °C, displaying excellent cycle stability and high capacitance retention at elevated voltages. Supercapacitors with PSNBF4/AN retain 96.6 % of their capacitance at 3.2 V, while PSNBF4/PN retained 93.4 % of their capacitance at 3.4 V after floating for 500 h. These results demonstrate PSNBF4-based supercapacitors can operate effectively at high voltages in both room and extremely low temperatures, addressing a significant challenge in commercial supercapacitor applications.

Iron Doping of 2D Nickel-Based Metal-Organic Frameworks Enhances the Lattice Heterogeneous Interface Coupling Effect for Improved Electrocatalytic Oxygen Evolution.

The coupling of lattice and heterostructure interfaces represents an effective strategy for disrupting the so-called scalar relationship and accelerating reactions involving multiple intermediates. In view of this, a lattice-heterostructure interfacial catalyst consisting of a crystalline Fe/Ni bimetallic MOF and amorphous Fe-MOF was designed in this paper for high-performance alkaline oxygen evolution reaction electrocatalysis. The strongly coupled lattice-heterostructure interface induces a unique synergistic effect that promotes electron transfer of the catalyst. The resulting catalyst exhibits exceptionally high catalytic activity for the oxygen evolution reaction in alkaline media, the Ni9Fe1-BDC-1@Fe-MOF coated on a glassy carbon electrode has an overpotential of 257 mV at a current density of 10 mA cm-2. Furthermore, this catalyst demonstrates a high electrochemical stability. These research results highlight the superiority of lattice-heterostructure interfaces in the development of advanced catalysts.

A Highly Compatible Deep Eutectic Solvent-Based Poly(ethylene) Oxide Polymer Electrolyte to Enable the Stable Operation of 4.5V Lithium Metal Batteries.

Insufficient ionic conductivity, limited Li+ transfer number (tLi+), and narrow electrochemical windows have heavily restricted the actual application of PEO （poly(ethylene) oxide）-based polymer electrolytes (PEs). Herein, a novel deep eutectic solvent (DES)-based PEO PE for stabilizing high voltage lithium metal battery (LMB) is designed. The DES reduces the crystallinity of PEO while promoting the dissociation of LiTFSI to release more free Li+, thus facilitating the transport of Li+ in the PEO matrix. In addition, the interaction between DES and the PEO, thereby improving the stability of the PEO-based PE under high voltage. Consequently, the PEO-DES-FEC (for short PDF) PE possesses satisfactory ionic conductivity, good mechanical properties, and high electrochemical stability. Meanwhile, PDF PE can build a robust/uniform LiF-rich solid electrolyte interface (SEI) to ensure electrode/electrolyte interface stability. As a concept proof, the Li symmetrical battery and Li||LiFePO4 LMBs of PDF PE exhibit good cycle stability. Applied to the high voltage Li||NCM811 LMBs, the PDF PE-based cell has excellent cycling performance at 4.3 and 4.5V. This tactic is one of the successful demonstrations of PEO-based electrolytes under 4.5V high voltage conditions, which breaks through the voltage constraint of conventional PEO-based PEs.

Synergistic modification of Ti/PbO2 electrodes with metal ions (Nd, Al, Bi) and STAB surfactant for electrocatalytic treatment of desulfurization wastewater

In this study, PbO2 electrodes are modified by co-doping with different metallic elements (Nd, Al, Bi) and stearyl trimethyl ammonium bromide (STAB) using the electrodeposition method. The modified electrodes, designated as Ti/PbO2-Nd-STAB, Ti/PbO2-Al-STAB, and Ti/PbO2-Bi-STAB, are then applied in the electrochemical degradation of desulfurization wastewater. The surface morphology, crystal structure, and elemental valence of the prepared electrodes are analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Their electrochemical performance and stability are assessed by linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and accelerated life testing (ALT). The results reveal that modification with metallic elements and STAB significantly enhances the physicochemical and electrocatalytic performance of the Ti/PbO2 electrode. Among the modified electrodes, the Ti/PbO2-Nd-STAB electrode exhibits the most compact and homogeneous surface morphology, the highest oxygen evolution potential (OEP, 2.33 V vs. SCE), the lowest chlorine evolution potential (CEP, 1.44 V vs. SCE), the largest electrochemically active surface area, the lowest charge transfer resistance, the highest electrochemical stability, and a prolonged accelerated life (65 h, which is 17 h longer than that of the unmodified electrode). Further, the optimal electrochemical oxidation process parameters for desulfurization wastewater are determined as follows: current density = 50 mA/cm2, temperature = 35 ℃, electrode spacing = 3.0 cm, and stirring rate = 300 rpm. After 300 min of electrolysis, the Ti/PbO2-Nd-STAB electrode achieves a Cl− removal rate of 86.9 % and a chemical oxygen demand (COD) removal rate of 71.2 %. After 10 cycles, the Cl− and COD removal rates decrease by 2.8 % and 1.8 %, respectively. Besides, Tafel curve analysis indicates that the chlorine evolution reaction follows the Volmer-Tafel mechanism, with the recombination of adsorbed Cl− ions on the surface oxidation film being the rate-determining step. Overall, the Ti/PbO2-Nd-STAB anode exhibits immense application potential in the treatment of desulfurization wastewater.

Composite Gel Polymer Electrolyte for High-Performance Flexible Zinc-Air Batteries.

Enhancing ionic conductivity and electrolyte uptake is of significance for gel polymer electrolytes (GPEs) for flexible zinc-air batteries (FZABs). Herein, a composite mesoporous silica/polyacrylamide (5 wt.% mPAM) GPE is constructed with comparable ionic conductivity to aqueous electrolytes, where the ionic conductivity is up to 337 mS cm-1, and the weight loss after exposing in air 72h is less than 18%, owing to the excellent electrolyte uptake and continuous ion migration network provided by the mesoporous silica fillers. When used as a quasi-solid-electrolyte, the rechargeable FZAB exhibited high electrochemical performance and structural stability, where the peak power density is up to 162.8mW cm-2, and the initial charge-discharge potential gap is as low as 0.62V, resulting in a long lifespan exceeding 110h, showcasing the combination of high durability, cost-effectiveness and easy production for practical applications.

Unveiling the potential of lithium fluoride phosphate (Li2MPO4F, M = Fe, V, Mn) for the next generation of lithium-ion batteries: A comparative study based on first principles and molecular dynamic simulations

LiFePO4 (LFP) cathode with olivine crystal structure has been a key player in safe and affordable energy storage, owing to its low-cost iron and high electrochemical stability within a voltage range of commercial electrolytes (2.8–3.4 V). To maintain these benefits while enhancing its energy density, Li2MPO4F was developed by introducing fluorine (F) and replacing iron with other transition metals (M). However, previous studies on these materials primarily measured performance within a limited voltage window (e.g., 2.5–4.5 V), making it challenging to analyze their performance under advanced electrolytes with a broader voltage range. In this study, we took a novel approach by utilizing first principles and molecular dynamic calculations to investigate the electrochemical performance of Li2MPO4F with three types of transition metals (M = V, Fe, Mn). This unique methodology, which includes calculations on theoretical voltages, atomic structures, and diffusion coefficient after structural optimization, allowed us to predict the impact of transition metals on cathode performance. By closely comparing the expected results, this study discusses the pros and cons of each cation substitution and suggests suitable cathode materials for batteries with high energy density and superior rate capability.

Gel interface for garnet-based lithium metal batteries with high loading cathode

Garnet-type electrolytes are ideal for lithium-metal batteries due to their high ionic conductivity and electrochemical stability. However, high interfacial resistance caused by poor contact with electrodes remains a challenge. To address this, we developed a flexible gel interlayer via in-situ polymerization to improve interface contact and reduce impedance. Additionally, a thick cathode with a laser-drilled channel structure was constructed to enhance gel electrolyte penetration and discharge capacity. Consequently, the Li/GEL-LLZTO-GEL/Li symmetric cell achieved a critical current density of 1.5 mA cm−2 and a reduced interfacial resistance of 134 O at room temperature. The quasi-solid half-cell with the laser-drilled cathode maintained a discharge capacity of 132.4 mAh/g with an active material loading of 13.1 mg cm−2 after 100 cycles. This work provides a simple and effective method for manufacturing safe and stable lithium metal batteries.

Electroactive ferrocene-based ionic liquids: transport and electrochemical properties of their acetonitrile solutions

The increasing global demand for energy stimulates the development of advanced energy storage and conversion technologies. Modification of electrolyte with redox-active additives is a promising way to enhance the electrochemical performance of energy storage devices. In this work new electroactive ferrocene-based ionic liquids (Fc-ILs) (N-methyl-N-(ferrocenylmethyl)piperidinium bis(trifluoromethanesulfonyl)imide [PipFcMe][NTf2], N-methyl-N-(ferrocenylmethyl)pyrrolidinium bis(trifluoromethanesulfonyl)imide [PyrFcMe][NTf2], N-ethyl-N-(ferrocenylmethyl)pyrrolidinium bis(trifluoromethanesulfonyl)imide [PyrFcEt][NTf2]) were synthesized. The structure of the Fc-ILs was confirmed by NMR and XRD. [PipFcMe][NTf2] and [PyrFcMe][NTf2] demonstrated nearly similar crystal structures consisting of cation and anion columns, while alternating cation and anion layers are stacked in the [PyrFcEt][NTf2] crystal. The effects of the Fc-IL mole fraction and temperature on the transport properties of the acetonitrile solutions of the Fc-ILs have been established. The highest electrical conductivities of the [PipFcMe][NTf2], [PyrFcEt][NTf2] and [PyrFcMe][NTf2] solutions calculated using the Casteel-Amis equation were, respectively, 38.06 ± 0.63, 40.34 ± 0.93 and 41.09 ± 0.58 mS/cm at 348.15 K. The activation energies of conductivity were calculated using the Arrhenius and Vogel-Fulcher-Tamman approaches. The Fc-ILs demonstrated a high electrochemical stability range up to 4.67 V. The introduction of electron-withdrawing substituents into the cyclopentadienyl ring of Fc-ILs shifted the half-wave potential to the positive direction. The diffusion coefficients were calculated using the Randles–Ševčík equation for a quasi-reversible process.

Fluorine-Free Cycloaliphatic Epoxy-Based Siloxane Nanohybrid Binder with High Polar Hydroxyl Group Content Enabling LiFePO4-Type Battery with High Electrochemical Performance and Stability.

LiFePO4-type (LFP) batteries have attracted significant attention in most battery manufacturing industries due to their long lifespan, high-temperature safety, and low cost of raw materials. However, as an active material, LFP still suffers from several intrinsic drawbacks, including poor conductivity, a low Li+ diffusion coefficient, low capacity, and a lack of electrochemical stability, primarily due to conventional fluorine-based binders. Here, we report a simple yet effective approach to developing a fluorine-free binder based on a robust cycloaliphatic epoxy-based siloxane nanohybrid material (CES) to achieve high electrochemical stability in LFP batteries. The high content of silanol moieties in CES induces a strong affinity for the active material and conductive agent, significantly improving rheological (thixotropy) and mechanical (adhesion and cohesion) properties, which enable the formation of a uniformly coated electrode. As a result, we achieved superior electrochemical performance and stability in CES-applied electrodes compared to those with conventional fluorine-based binders. We investigate the reasons behind the contribution of CES to the electrochemical stability of LFP batteries through various analyses. The high thermal and oxidation stability of CES effectively prevents degradation of LFP-based active materials. Our binder development strategy offers a significant breakthrough in replacing conventional fluorine-based binders, advancing the development of high-performance and stable secondary batteries.

Poly(3, 4-Ethylenedioxythiophene) as Promising Energy Storage Materials in Zinc-Ion Batteries.

Benefiting from the advantages of high conductivity and good electrochemical stability, the conjugated conducting polymer poly (3, 4-ethylenedioxythiophene) is a promising energy storage material in zinc-ion batteries. Zinc-ion batteries have the advantages of high safety, environmental friendliness, and low cost, but suffer from unstable cathode material structure, poor electrical conductivity, and uncontrollable dendritic growth of zinc anodes. PEDOT, with its fast electrochemical response and wide potential window, is expected to make up for the shortcomings and enhance capacity and cycle life of zinc-ion batteries. Herein, in this review different polymerization methods of poly (3, 4-ethylenedioxythiophene) as well as their structure and properties are summarized; the progress in doping strategies related to the increasing conductivity and dispersivity of poly (3, 4-ethylenedioxythiophene) materials is discussed; specific applications of poly (3, 4-ethylenedioxythiophene)-based materials in anode, cathode, electrolyte, and binder of zinc-ion batteries are explored; and the representative advancements for improving the electrochemical performance of poly (3, 4-ethylenedioxythiophene) in zinc-ion batteries are emphasized. Finally, the current challenges of poly (3, 4-ethylenedioxythiophene) as promising materials in zinc-ion batteries and an insight into their future research directions are pointed out.

Cascaded utilization of magnetite nanoparticles@onion-like carbons from wastewater purification to supercapacitive energy storage.

Developing high-performance carbon-based materials for environmental and energy-related applications produces solid waste with secondary pollution to the environment at the end of their service lives. It is still challenging to utilize these functional materials in a sustainable manner in different fields. In this study, we demonstrate a cascaded utilization of an Fe3O4@onion-like carbon (Fe3O4@OLC) structure from wastewater adsorbents to a supercapacitor electrode. The structure was formed by carbonizing Fe3O4@oleic acid monodisperse nanoparticles into interconnected Fe3O4@OLCs and subsequent insufficient acid etching. The hollow OLCs in the outside region of the hybrid structure provide high surface area and the encapsulated Fe3O4 nanoparticles in the inside region offer high ferromagnetism. The three-dimensionally interconnected graphitic layers are advantageous for efficient separation and high conductivity. As a result, the maximum saturation adsorption capacity of insufficiently etched interconnected Fe3O4@OLCs can reach up to 90.2 mg g-1 and they can be efficiently separated under a magnetic field. Furthermore, the hybrid structure is thermally transformed into N-doped HOLCs, which are demonstrated to be a high-performance supercapacitor electrode with high specific capacitance and high electrochemical stability. The cascaded utilization of the hybrid structure in this study is meaningful for eco-friendly development of functional materials for environmental and energy storage applications.

Organic Cationic-Coordinated Perfluoropolymer Electrolytes with Strong Li+-Solvent Interaction for Solid State Li-Metal Batteries.

The practical application of solid-state polymer lithium-metal batteries (LMBs) is plagued by the inferior ionic conductivity of the applied polymer electrolytes (PEs), which is caused by the coupling of ion transport with the motion of polymer segments. Here, solvated molecules based on ionic liquid and lithium salt with strong Li+-solvent interaction are inserted into an elaborately engineered perfluoropolymer electrolyte via ionic dipole interaction, extensively facilitating Li+ transport and improving mechanical properties. The intensified formation of solvation structures of contact ion pairs and ionic aggregates, as well as the strong electron-withdrawal properties of the F atoms in perfluoropolymers, give the PE high electrochemical stability and excellent interfacial stability. As a result, Li||Li symmetric cells demonstrate a lifetime of 2500 h and an exceptionally high critical current density above 2.3 mA cm-2, Li||LiFePO4 batteries exhibit consistent cycling for 550 cycles at 10 C, and Li||uncoated LiNi0.8Co0.1Mn0.1O2 cells achieve 1000 cycles at 0.5 C with an average Coulombic efficiency of 98.45 %, one of the best results reported to date based on PEs. Our discovery sheds fresh light on the targeted synergistic regulation of the electro-chemo-mechanical properties of PEs to extend the cycle life of LMBs.

Organic Cationic‐Coordinated Perfluoropolymer Electrolytes with Strong Li+‐Solvent Interaction for Solid State Li‐Metal Batteries

AbstractThe practical application of solid‐state polymer lithium‐metal batteries (LMBs) is plagued by the inferior ionic conductivity of the applied polymer electrolytes (PEs), which is caused by the coupling of ion transport with the motion of polymer segments. Here, solvated molecules based on ionic liquid and lithium salt with strong Li+‐solvent interaction are inserted into an elaborately engineered perfluoropolymer electrolyte via ionic dipole interaction, extensively facilitating Li+ transport and improving mechanical properties. The intensified formation of solvation structures of contact ion pairs and ionic aggregates, as well as the strong electron‐withdrawal properties of the F atoms in perfluoropolymers, give the PE high electrochemical stability and excellent interfacial stability. As a result, Li||Li symmetric cells demonstrate a lifetime of 2500 h and an exceptionally high critical current density above 2.3 mA cm−2, Li||LiFePO4 batteries exhibit consistent cycling for 550 cycles at 10 C, and Li||uncoated LiNi0.8Co0.1Mn0.1O2 cells achieve 1000 cycles at 0.5 C with an average Coulombic efficiency of 98.45 %, one of the best results reported to date based on PEs. Our discovery sheds fresh light on the targeted synergistic regulation of the electro‐chemo‐mechanical properties of PEs to extend the cycle life of LMBs.

Anion and Cation Dynamics in Mixed-Anion Hydroborate Na3(BH4)(B12H12): 1H, 11B, and 23Na NMR Studies

Sodium borohydride-closo-hydroborate Na3(BH4)(B12H12) exhibits high room-temperature ionic conductivity and high electrochemical stability. To study the dynamical properties of this mixed-anion compound at the microscopic level, we have measured the 1H, 11B, and 23Na nuclear magnetic resonance spectra and nuclear spin-lattice relaxation rates over the temperature range of 8–573 K. Our 1H and 11B spin-lattice relaxation measurements have revealed two types of reorientational jump motion. The faster motional process attributed to reorientations of the [BH4]− anions is characterized by an activation energy of 159 meV, and the corresponding reorientational jump rate reaches ~108 s−1 near 130 K. The slower process ascribed to reorientations of the larger [B12H12]− anions is characterized by an activation energy of 319 meV, and the corresponding reorientational jump rate reaches ~108 s−1 near 240 K. The results of the 23Na nuclear magnetic resonance measurements are consistent with the fast long-range diffusion of Na+ ions in Na3(BH4)(B12H12). The diffusive jump rate of Na+ is found to reach ~104 s−1 at 300 K and ~8 × 108 s−1 at 530 K. A comparison of these jump rates with the ionic conductivity data suggests the importance of correlations between diffusing ions.

Li-Fe-Cl Families as Novel Solid Electrolytes for All-Solid-State Batteries.

The halides have attracted much attention as novel solid electrolytes because of their easy synthesis, high electrochemical stability, and high ionic conductivities. However, the reported halides for solid electrolytes are still understudied compared with the oxides and sulfides. Here, we studied the Li-Fe-Cl phases that include Li2FeCl4 and Li6FeCl8. Using the self-doping approach, a maximum ionic conductivity of 2.0 × 10-4 S cm-1 at 50 °C was achieved for Li1.8Fe1.1Cl4. It was improved by 3 orders of magnitude compared with that of Li2FeCl4 (8.27 × 10-7 S cm-1 at 50 °C). For the Li|Li1.8Fe1.1Cl4|Li half-cell, it cycled for 2000 h at 50 °C under a current density of 0.01 mA cm-2, indicating an acceptable compatibility between Li2FeCl4 and Li. Finally, an all-solid-state battery was successfully assembled with Li1.8Fe1.1Cl4@LFP as the cathode, Li1.8Fe1.1Cl4 as the electrolyte, and a Li sheet as the anode. The initial specific charge capacity of the battery was 76.36 mAh g-1 at 0.1C and 50 °C. The initial Coulombic efficiency was 73.06%. This study suggests Li2FeCl4 as a new solid electrolyte, and the introduction of Li vacancies into the Li site is an efficient way to improve the electrochemical properties of halides.

Bio-derived gel polymer electrolytes from zein and honey blends integrated with ammonium nitrate for electrical double layer capacitors

Although electrical double layer capacitors (EDLCs) are known to exhibit impressive power density, rapid charging/discharging, and long cycle life, their energy density remains a hurdle for broader use. Gel polymer electrolytes (GPEs) offer an interesting approach to improve the energy density of EDLCs while maintaining their other desirable characteristics. This study investigates the development of novel GPEs based on zein, honey, and ammonium nitrate (NH4NO3) for EDLC applications. The GPEs are prepared by incorporating zein, honey, and NH4NO3 in a dimethyl sulfoxide (DMSO) solvent system through a solution casting method. The degree of crystallinity of zein successfully reduced from 33.0 % to 15.71 % with the addition of 20 wt% NH4NO3. The interaction between zein, honey and NH4NO3 is confirmed by observing the shifting of the hydroxyl band. The ambient ionic conductivity of zein-honey increases from (4.86 ± 0.36) × 10−4 S cm−1 to (4.19 ± 0.40) × 10−3 S cm−1 with the incorporation of 20 wt% NH4NO3 (ZH20), exhibiting the significantly lowest Tg value (77.53 °C). Linear sweep voltammetry (LSV) demonstrates high electrochemical stability up to 2.6 V of ZH20. Additionally, the transference number (tion) of 0.989 indicates a dominant role of ionic charge carriers in this work. Finally, the ZH20-based GPE is used as both an electrolyte and separator to fabricate EDLC. Its electrochemical behavior has demonstrated stable results in terms of specific capacitance, energy, and power density, with fast rate performance observed through cyclic voltammetry and galvanostatic charge-discharge techniques.

Preparation of polyelectrolyte based on bottle brush Polyethylene glycol‐Poly(N‐isopropylacrylamide) copolymers

AbstractThe increased demand for high energy‐density batteries led to using lithium metal (Li) anode. However, safety issues associated with Li anode encouraged the researchers to use less reactive and safer electrolytes with higher electrochemical stability. High ionic conductivity (σ), wider electrochemical stability window, and higher mechanical strength alongside the ability to self‐heal possible structural damages were at the center of focus for developing efficient solid electrolytes. In this regard, we developed a group of solid polymer electrolytes (SPEs) with high σ and electrochemical stability. In this regard, bottle brush polyethylene glycol (bbPEG) was synthesized using a chain transfer reaction. Polynipaam (PNIPAAM) blocks were also incorporated into the structure to prepare a block copolymer based on PNIPAM‐bbPEG‐PNIMAM represented by the ABA structure. The block copolymer was then blended with polyvinylidene fluoride (PVDF) with the block copolymer to PVDF weight ratio of 7:2% and 25% bis(trifluoromethane) sulfonamide (TFSI) salt was added and the final mixture was UV‐cured. The results indicated that the final SPE possessed high ionic conductivity with a relatively high lithium‐ion transference number () of 0.416 and the σ of 1.265 × 10−5 S/cm at 25°C.

Ruddlesden-Popper perovskite anode with high sulfur tolerance and electrochemical activity for solid oxide fuel cells

Solid oxide fuel cells (SOFCs) are regarded as attractive electrochemical energy conversion devices owing to their exceptional efficiencies and superb fuel flexibility. However, their widespread implementations are remarkably restricted by the inferior sulfur tolerance of state-of-the-art nickel-based cermet anodes under practical conditions. Herein, a layered NaLaTiO4 (NLTO) perovskite oxide with Ruddlesden-Popper structure is designed as a new anode for SOFCs operating on sulfur-containing fuels. After impregnating NLTO into a samaria-doped ceria (SDC) scaffold, such impregnated nanocomposite anode exhibits high electrochemical activity, sulfur tolerance and stability in H2S-containing fuels due to the polar layered structure, abundant oxygen vacancies, superior surface basicity and water storage capability, leading to the efficient removal of the deposited/adsorbed sulfur on the surface of this nanocomposite anode. The electrochemical activity of the NLTO-based composite anode for fuel oxidation is further improved by adding nickel nanoparticles through impregnation, showing enhanced power outputs and considerable operational stability in H2S-containing fuels. This study provides a new, high-performing and sulfur-resistant anode for SOFCs, which may promote the commercialization of this technology.