Ionic Behavior Research Articles

Ionic Conductivity and Aggregation Behavior of N,N-Dimethylethanolammonium Carboxylate Protic Ionic Liquids in Aqueous, Ethanolic, and Acetonitrile Solutions

Ionic Conductivity and Aggregation Behavior of N,N-Dimethylethanolammonium Carboxylate Protic Ionic Liquids in Aqueous, Ethanolic, and Acetonitrile Solutions

Exploration of physical, structural, thermal, and optical properties of alkali zinc boro tellurite glasses doped with europium trioxide

In this present work we have studied the physical, structural, thermal, and optical properties of a new set of alkali zinc boro tellurite glasses doped europium trioxide prepared using the melt-quenching method. X-ray diffraction technique (XRD) and SEM were used to determine the non-crystalline property and microstructure property of the prepared samples. By using MAS-NMR spectroscopy and FTIR spectroscopy, the structural changes in the glasses were revealed. The physical properties were described by considering the densities of glass samples and hence molar volume, polaron radius, and oxygen packing density were measured. Thermal stability of glasses was perceived by performing DSC analysis and values ranges from 145 to 190 °C. Using UV–visible absorption spectra, it was possible to calculate the optical properties. The highest refractive index is found as 2.275 for glass AZBTE0 and the lowest is 2.241 for AZBTE5 glass. The ionic behaviour of the glasses was determined by electronegativity and values lie in the range of 1.51 to 1.688. The outcomes of the physical, thermal, and optical characteristics of glasses are intended for potential uses in optical switching and Europium doped fibre amplifier applications.

A seaweed-inspired separator for high performance Zn metal batteries: Boosting kinetics and confining side-reactions

Uncontrolled dendrite growth, sluggish reaction kinetics, and drastic side reactions on the anode-electrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion batteries. Traditional glass fiber (GF) separator with chemical inertness is almost ineffective in restricting these challenges. Herein, inspired by the ionic enrichment behavior of seaweed plants, a facile biomass species, anionic sodium alginate (SA), is purposely decorated on the commercial GF separator to tackle these issues towards Zn anode. Benefiting from the abundant zincophilic functional groups and superior mechanical strength properties, the as-obtained SA@GF separator could act as ion pump to boost the Zn2+ transference number (0.68), reduce the de-solvation energy barrier of hydrated Zn2+, and eliminate the undesired concentration polarization effect, which are verified by experimental tests, theoretical calculations, and finite element simulation, respectively. Based on these efficient modulation mechanisms, the SA@GF separator can synchronously achieve well-aligned Zn deposition and the suppression of parasitic side-reactions. Therefore, the Zn||Zn coin cell integrated with SA@GF separator could yield a prolonged calendar lifespan over 1230 h (1 mA cm−2 and 1 mAh cm−2), exhibiting favorable competitiveness with previously reported separator modification strategies. Impressively, the Zn-MnO2 full and pouch cell assembled with the SA@GF separator also delivered superior cycling stability and rate performance, further verifying its practical application effect. This work provides a new design philosophy to stabilize the Zn anode from the aspect of separator.

Dependence of Carboxylate Anions on Physicochemical Properties of Tributyloctylphosphonium-Based Ionic Liquids

A new group of tributyloctylphosphonium-based ionic liquids containing several carboxylate anions was designed, prepared and physicochemically characterized. All phosphonium carboxylates obtained in this study became viscous liquids at room temperature. The formate-based ionic liquid exhibited the highest density and number density due to the smallest anion size. All ionic liquids exhibited typical ionic conduction behavior, since the viscosity decreased and the conductivity increased with increasing temperature. It was also found that the viscosity tended to decrease with increasing the carbon numbers of the alkyl chains of lower carboxylate anions. Compared to the propionate-based ionic liquids, lactate-based ionic liquids exhibited higher viscosity. The phosphonium ionic liquids based on carboxylate anions showed higher thermal stability than nitrogen-based counterpart ionic liquids.

Behaviour of ionic herbicides in different forestry soils derived from volcanic ash

Background: Weed control has been one of the most significant factors in forest establishment practices that can improve biomass production, and herbicides represent the most effective and convenient way to control weeds. The environmental concern about herbicides in this industry is because the herbicide-treated area is often located near water reservoirs or areas where rivers and creeks originate. This study aimed to determine the adsorption and degradation behaviours of seven ionic herbicides used in forestry production in five Chilean forestry soils and their relation to the leaching and to generate information to validate environmental predictive models. Methods: Adsorption and degradation of ionisable herbicides such as simazine, terbuthylazine, hexazinone, metsulfuron-methyl, indaziflam, flazasulfuron and glyphosate were studied in Andisol, Ultisol, Inceptisol, Entisol and Alfisol forestry soils, to be related to their leaching in 100-cm high and 11-cm diameter soil disturbed lysimeters. Herbicides were quantified using high-pressure liquid chromatography and gas chromatography. Relationships between soil physicochemical properties, herbicide adsorption and degradation, and herbicide leaching were determined. Results: In decreasing order, the herbicides were mobile in Entisol>Alfisol>Ultisol>Inceptisol>Andisol soils. On the other hand, the more leachable herbicides, from high to low, were: hexazinone, metsulfuron-methyl, simazine, glyphosate, terbuthylazine, flazasulfuron and indaziflam. The last two herbicides were not detected below 60 cm soil depth. In general, the maximum soil depth herbicide reached and the percentage mass leached up to 90 cm soil depth were inversely related to soil adsorption (1/Kd), soil porosity, humidity, silt, aluminium, and calcium soil content. Herbicide degradations were generally faster than referential published values. Conclusions: The environmental coefficients of ionic herbicides were more related to soil properties than their physicochemical properties. Persistence of herbicides in soil was smaller than that commonly reported in other studies or international databases and soil adsorption averages were generally higher than international reference values. The stronger relationship between ionic herbicide behaviour and forestry soil properties endorses the requirement to determine the environmental herbicides parameters in situ, avoiding using parameters estimated in other soils.

Enhancing the Performance of Nanocrystalline SnO2 for Solar Cells through Photonic Curing Using Impedance Spectroscopy Analysis.

Wide-bandgap tin oxide (SnO2) thin-films are frequently used as an electron-transporting layers in perovskite solar cells due to their superior thermal and environmental stabilities. However, its crystallization by conventional thermal methods typically requires high temperatures and long periods of time. These post-processing conditions severely limit the choice of substrates and reduce the large-scale manufacturing capabilities. This work describes the intense-pulsed-light-induced crystallization of SnO2 thin-films using only 500 μs of exposure time. The thin-films' properties are investigated using both impedance spectroscopy and photoconductivity characteristic measurements. A Nyquist plot analysis establishes that the process parameters have a significant impact on the electronic and ionic behaviors of the SnO2 films. Most importantly, we demonstrate that light-induced crystallization yields improved topography and excellent electrical properties through enhanced charge transfer, improved interfacial morphology, and better ohmic contact compared to thermally annealed (TA) SnO2 films.

Improved electrical properties of Ba1−xCaxCe0.8Nd0.2O3−δ solid oxide fuel cells

Among the most effective proton-conducting oxides for use as electrolytes in fuel and electrolysis cells that are all solid-state are barium cerates. The sol–gel auto-combustion synthesis method synthesised electrolytes of the formula Ba1−xCaxCe0.8Nd0.2O3−δ where x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.10. XRD, SEM, FTIR, and Raman analysis were done to determine the structure, surface morphology, and bond-stretching vibrations. According to Scherer’s formula, the electrolyte materials’ anticipated crystallite sizes ranged from 20.14 to 36.50 nm. Grain sizes were in the range from 2.5 to 4.5 µm. While FT-IR detected bands related to M–O vibrations, the 362.51 cm−1 vibrational mode related to CeO6 octahedra was identified by Raman spectroscopy. Electrical impedance spectroscopy studies confirmed electrolytes had good ionic behavior, with total conductivities increasing with temperature. The bulk conductivity of the studied perovskite oxides was higher than grain boundary conductivity, with compositions with x = 0.10 exhibiting the maximum overall conductivity.

Unveiling Gating Behavior in Piezoionic Effect: toward Neuromimetic Tactile Sensing.

The human perception system's information processing is intricately linked to the nonlinear response and gating effect of neurons. While piezoionics holds potential in emulating the pressure sensing capability of biological skin, the incorporation of information processing functions seems neglected. Here, ionic gating behavior in piezoionic hydrogels is uncovered as a notable extension beyond the previously observed linear responses. The hydrogel can generate remarkably high voltages (700mV) and currents (7mA) when indentation forces surpass the threshold. Through a comprehensive analysis involving simulations and experimental investigations, it is proposed that the gating behavior emerges due to significant diffusion differences between cations and anions. To showcase the practical implications of this breakthrough, the piezoionic hydrogels are successfully integrated with prostheses and robot hands, demonstrating that the gating effect enables accurate discrimination between gentle and harsh touch. The advancement in neuromimetic tactile sensing has significant potential for emerging applications such as humanoid robotics and biomedical engineering, offering valuable opportunities for further development of embodied neuromorphic intelligence.

GIS-Based Mapping of the Water Quality and Geochemical Assessment of the Ionic Behavior in the Groundwater Aquifers of Middle Ganga Basin, Patna, India

The study implemented Geographic Information System (GIS) techniques and multivariate hydrogeochemical analysis to evaluate the spatial-temporal and seasonal variation in the groundwater quality of Patna, India. For this purpose, sixty groundwater samples were collected and analyzed for major anions and cations during the pre-monsoon, monsoon, and post-monsoon seasons of 2019-2020. The physicochemical parameters such as pH, EC (Electrical Conductivity), TDS (Total Dissolved Solids), TH (Total Hardness), Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42- were considered to evaluate the water quality index. The result revealed degradation in groundwater quality from pre-monsoon (49.21) to post-monsoon (74.48). EC, TDS, TH, Mg2+, Na+, Ca2+, K+, and HCO3- ions were found accountable for high WQI values at various sampling sites during different seasons. Spatial maps showed that 45 % of the sampling stations exhibited poor quality in all three seasons, where the eastern part of the studied region was revealed to be the most affected area. The application of multivariate statistical methods and hydrogeochemical investigation has clearly defined the dominant role of the weathering process, and reverse ion exchange mechanism in controlling the aquifer’s ionic chemistry. Moreover, poor seepage system, and waste leachate from the surface have been found as the main cause of high levels of Na+, K+, and Cl- in the eastern part of Patna.

Spectral and conductivity measurements insights on loading mechanisms of DMSO/water-kaolin complexes

Kaolin, a naturally occurring clay mineral renowned for its distinctive properties, holds significant importance across various industries. The integration of dimethyl sulfoxide (DMSO) into kaolin matrices, both in the presence and absence of water, has been extensively explored for its potential to enhance material characteristics. Addressing debates surrounding the proposed adsorption mechanism for the type I structure of DMSO, this study undertook a comprehensive physicochemical characterization of DMSO-kaolin complexes (DMSO-KCs) derived from untreated (UnK) and HCl-treated (HK) Egyptian ore, with a focus on elucidating the loading mechanism facilitated by water.Key insights gleaned from electrical conductivity, dielectric constant, and Fine Testing Technology – Fourier-transform infrared (FTT-FTIR) measurements, shedding light on the bonding nature of DMSO-KCs. FTT-FTIR analysis revealed two stages of water departure at 180 °C, with the final stage coinciding with the release of pyrolysis gases, confirming the catalytic degradation of DMSO. Through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), two distinct bonding types of DMSO molecules with kaolinite were identified: amorphous adsorbed (type I) and lattice-oriented intercalated (type II).Electrical characteristic evaluations within the temperature range of room temperature (RT) to 260 °C and frequency range of 42 Hz–1 MHz revealed that DMSO intercalation enhances the electrical properties of kaolin. Hydrated DMSO-KCs exhibited higher values of σac and ɛʹ compared to non-hydrated samples. The activation energy (Ea) values for HCl-treated samples were smaller than those of untreated ones. Alternating current (AC) conductivity analysis indicated predominantly ionic behavior with frequency and temperature dependency in both HCl-treated and untreated kaolin. Our findings substantiate the adsorption mechanism of Type I DMSO, highlighting its amorphous nature, instability, and catalytic degradation over time, in contrast to the intercalated type II. This elucidation is pivotal for understanding the behavior of DMSO-KCs across diverse applications, including electronics, ceramics, and materialsscience.

Computational Analysis of Ion Clustering Statistics in Liquid Battery Electrolytes

The transport properties of liquid battery electrolytes critically depend on molecular-level solvation structures of ions. In contrast to the dilute regime where the majority of counterions are sufficiently separated spatially, in global or localized high-concentrated electrolytes (HCEs) counterions tend to form superstructures such as contact-ion pairs (CIPs) or aggregates (AGGs). The presence and relative population of such superstructures can drastically change the ionic transport behavior in liquid electrolytes. We have developed a computer program [1] that can efficiently perform analysis of ion clustering statistics from molecular dynamics simulations, complementary to experimental measurements. We have successfully applied our method to various systems, including (1) a prototypical concentrated liquid electrolyte (Li:EC:DEC) [2], and (2) a series of newly developed high-entropy liquid electrolytes [3]. In both cases, we find consistent agreements between our prediction and experimentally measured nanostructures and solvation strengths. We envision that our method would be widely applicable to generic structurally disordered systems.[1] Cohen et al., Journal of Open Source Software 8, 84 (2023)[2] Xie and Wang et al., Science Advances 9, eadc9721 (2023)[3] Kim and Wang et al. Nature Energy 8, 814–826 (2023)

Exploring the Relationship between Interfacial Chemistry and Thermal Safety of a Flame Retarding Semisolid Electrolyte

The safety-related performance of LIBs still remains as a major issue even after more than three decades of commercialization.1 When typical electrolytes composed of flammable organic liquid solvents vaporize and decompose exothermically during thermal runaway, they pose serious risk to human health and infrastructure.2 Conventional lithium-ion batteries (LIBs) are energy storage devices which function as electrochemical systems subject to highly dynamic heterogeneous reaction phenomena. As a result, the tolerance levels of tangible harm to users and surrounding environments may be amplified considerably as scale and pervasiveness of technology increases. Beyond consumer devices, large-scale energy storage to complement renewable power generation technologies is instrumental to the goal of decarbonization via electrification and thus global goals for carbon neutrality in the 21st century. Renewable power generation benefits substantially from decoupling the spatial and temporal points of energy generation from that of demand.Recent efforts in academia and industry alike have endeavored to replace volatile and flammable conventional liquid electrolytes (composed of classes of compounds such as carbonates or ethers) with intrinsically nonflammable liquid electrolytes (composed of fluorinated and phosphorus-containing organic solvents).3–5 Simultaneously, solid-state electrolytes have been touted as an avenue to not only wholly replace the liquid component of the cell to improve safety, but also as a higher-energy density next-generation battery electrolyte.6 However, these strategies are often examined as materials-level design choices for improving “built-in” safety and not as changes to a dynamic and multiscale electrochemical system.In this study, we find that the intrinsic safety of a system is highly dependent on the interfacial degradation pathways of the electrode-electrolyte configuration, which acts as a direct complement to the thermal behavior which may result in thermal runaway. Through detailed multimodal calorimetry and characterization of the interfacial composition, this work subsequently brings the question of flammability into focus as a downstream consequence of the interfacial reaction kinetics. This is accomplished through the combined efforts of thermal analyses as well as X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy accompanied with electron crystallography analyses, and nuclear magnetic resonance studies of the ionic transport behavior through the polymeric electrolyte. Through these efforts, design principles centered around holistic assessment of the lifespan of materials and their electrochemical and thermal interactions are developed towards the greater goal of improving the safety and resilience of LIBs and their devices against the wide spectrum of abuse scenarios created by their expanding application space.(1) Feng, X.; Ren, D.; He, X.; Ouyang, M. Mitigating Thermal Runaway of Lithium-Ion Batteries. Joule 2020, 4 (4), 743–770. https://doi.org/10.1016/j.joule.2020.02.010.(2) Wang, Q.; Jiang, L.; Yu, Y.; Sun, J. Progress of Enhancing the Safety of Lithium Ion Battery from the Electrolyte Aspect. Nano Energy 2019, 55, 93–114. https://doi.org/10.1016/j.nanoen.2018.10.035.(3) Cao, X.; Xu, Y.; Zhang, L.; Engelhard, M. H.; Zhong, L.; Ren, X.; Jia, H.; Liu, B.; Niu, C.; Matthews, B. E.; Wu, H.; Arey, B. W.; Wang, C.; Zhang, J.-G.; Xu, W. Nonflammable Electrolytes for Lithium Ion Batteries Enabled by Ultraconformal Passivation Interphases. ACS Energy Letters 2019. https://doi.org/10.1021/acsenergylett.9b01926.(4) Wang, J.; Yamada, Y.; Sodeyama, K.; Watanabe, E.; Takada, K.; Tateyama, Y.; Yamada, A. Fire-Extinguishing Organic Electrolytes for Safe Batteries. Nat Energy 2018, 3 (1), 22–29. https://doi.org/10.1038/s41560-017-0033-8.(5) Zheng, Q.; Yamada, Y.; Shang, R.; Ko, S.; Lee, Y.-Y.; Kim, K.; Nakamura, E.; Yamada, A. A Cyclic Phosphate-Based Battery Electrolyte for High Voltage and Safe Operation. Nat Energy 2020, 5 (4), 291–298. https://doi.org/10.1038/s41560-020-0567-z.(6) Janek, J.; Zeier, W. G. A Solid Future for Battery Development. Nat Energy 2016, 1 (9), 1–4. https://doi.org/10.1038/nenergy.2016.141

Monitoring Enzymatic Reaction Kinetics and Activity Assays in Confined Nanospace.

Enzyme-mediating biotransformations commonly occur in micro- and nanospace, which is crucial to maintain the essential biochemical processes and physiological functions in living systems. Probing enzyme-catalytic reactions in a biomimetic fashion remains challenging due to the lack of competent tools and methodology. Here, we show that studying enzymatic reaction kinetics can be readily achieved by a well-designed solid-state nanopore. Using tyrosine as a classical substrate, we quantitatively characterize the catalytic activity of tyrosinase (TYR) and tyrosine decarboxylase (TDC) in a nanoconfined space. Tyrosine was first immobilized in the nanopipette, wherein the active sites of tyrosine were left unoccupied. When successively exposed to TYR and TDC, a two-step cascade reaction can spontaneously take place. In this process, the surface wettability and charge of the nanopipette stemming from the catalytic products can sensitively regulate ion transport and ionic current rectification behavior, which were monitored by ionic current signal. In this biomimetic scenario, we obtained the enzymatic reaction kinetics of monophenyl oxidase that were not previously actualized in the conventional macroenvironment. Significantly, TYR showed higher enzyme activity, with a Km value of 1.59 mM, which was lower than that measured in a free and open space (with a Km of 3.01 mM). This suggests that tyrosine should be the most appropriate substrate of TYR, thus improving our understanding of tyrosine-associated biochemical reactions. This work offers an applicable technical platform to mimic enzyme-mediated biotransformations and biometabolisms.

Tetraethylammonium Perfluorobutanesulfonate as an Alternative Salt for Electric Double Layer Capacitors

AbstractThe utilization of tetraethylammonium perfluorobutane sulfonate as a promising alternative salt for electrolyte solutions in electrochemical double layer capacitors is introduced in this study. A thorough analysis of the physical and electrochemical characteristics of tetraethylammonium perfluorobutane sulfonate was conducted, including the assessment of its ionic conductivity, viscosity, and thermal behavior, using a 1 M solution in acetonitrile. Comparative assessments were made between the performance of this novel electrolyte and two well‐studied electrolytes: 1 M tetraethylammonium tetrafluoroborate and 1 M tetraethylammonium bis(trifluoromethanesulfonyl)imide in acetonitrile, focusing on electrochemical performance and long‐term stability. Furthermore, an investigation into the impact of tetraethylammonium perfluorobutane sulfonate on the anodic dissolution of aluminum current collectors was conducted. The results highlight the potential of tetraethylammonium perfluorobutane sulfonate as an effective replacement for bis(trifluoromethanesulfonyl)imide‐based electrolytes.

Intricate Ionic Behaviors in High-Performance Self-Powered Hydrothermal Chemical Generator Using Water and Iron (III) Gate.

Utilizing the ionic flux to generate voltage output has been confirmed as an effective way to meet the requirements of clean energy sources. Different from ionic thermoelectric (i-TE) and hydrovoltaic devices, a new hydrothermal chemical generator is designed by amorphous FeCl3 particles dispersing in MWCNT and unique ferric chloride or water gate. In the presence of gate, the special ion behaviors enable the cell to present a constant voltage of 0.60V lasting for over 96h without temperature difference. Combining the differences of cation concentration, humidity and temperature between the right and left side of sample, the maximum short-circuit current and power output can be obtained to 168.46µA and 28.11 µW, respectively. The generator also can utilize the low-grade heat to produce electricity wherein Seebeck coefficient is 6.79mV K-1. The emerged hydrothermal chemical generator offers a novel approach to utilize the low-grade heat, water and salt solution resources, which provides a simple, sustainable and low-cost strategy to realize energy supply.

Transforming an Ionic Conductor into an Electronic Conductor via Crystallization: In Situ Evolution of Transference Numbers and Structure in (La,Sr)(Ga,Fe)O3‐x Perovskite Thin Films

AbstractMixed‐conducting perovskites are workhorse electrochemically active materials, but typical high‐temperature processing compromises their catalytic activity and chemo‐mechanical integrity. Low‐temperature pulsed laser deposition of amorphous films plus mild thermal annealing is an emerging route to form homogeneous mixed conductors with exceptional catalytic activity, but little is known about the evolution of the oxide‐ion transport and transference numbers during crystallization. Here the coupled evolution of ionic and electronic transport behavior and structure in room‐temperature‐grown amorphous (La,Sr)(Ga,Fe)O3‐x films as they crystallize is explored. In situ ac‐impedance spectroscopy with and without blocking electrodes, simultaneous capturingsynchrotron‐grazing‐incidence X‐ray diffraction, dc polarization, transmission electron microscopy, and molecular dynamics simulations are combined to evaluate isothermal and non‐isothermal crystallization effects and the role of grain boundaries on transference numbers. Ionic conductivity increases by ≈2 orders of magnitude during crystallization, with even larger increases in electronic conductivity. Consequently, as crystallinity increases, LSGF transitions from a predominantly ionic conductor to a predominantly electronic conductor. The roles of evolving lattice structural order, microstructure, and defect chemistry are examined. Grain boundaries appear relatively nonblocking electronically but significantly blocking ionically. The results demonstrate that ionic transference numbers can be tailored over a wide range by tuning crystallinity and microstructure without having to change the cation composition.

Thermal behaviors and DC conductivity of linker spacer influence on polymerized ionic liquids with bis-imidazolium embedding in the backbone chain

A series of polymerized ionic liquids (PILs) with bis-imidazolium embedding into the backbone was designed to study the effect of linker spacers (C-2, C-4, C-6, and C-8) on their ionic conductivity and thermal behaviors. All PILs were prepared by step-growth polymerization using a modified Menshutkin reaction, where 1,1′-(1,4-butadiyl) bisimidazole (Bbim), was structurally modified by a series of bis-bromoacetates (1,1-(1,n-alkanediyl) bis(bromoacetate) (n = 2, 4, 6, and 8 correspond to 1,2-EBA, 1,4-BBA, 1,6-HBA, and 1,8-OBA, respectively). Interestingly, the density function theory (DFT)-derived complexation energy exhibits a correlation with spacer length, decreasing as the linker spacer increases. Moreover, shorter linker chains notably elevate the glass transition temperature (Tg). The room temperature dc-conductivity of C-8 is the highest (2.2 × 10–5 S/cm) among PILs with shorter linker chain lengths. These results indicate that PILs 1–4 have the potential to yield substantial ionic conductivity in a chain of flexible segments (low Tg), while exhibiting a decrease in complexation energy.

Response of Ionic Hydration Structure and Selective Transport Behavior to Aqueous Solution Chemistry during Nanofiltration.

The effect of aqueous solution chemistry on the ionic hydration structure and its corresponding nanofiltration (NF) selectivity is a research gap concerning ion-selective transport. In this study, the hydration distribution of two typical monovalent anions (Cl- and NO3-) under different aqueous solution chemical conditions and the corresponding transmembrane selectivity during NF were investigated by using in situ liquid time-of-flight secondary ion mass spectrometry in combination with molecular dynamics simulations. We demonstrate the inextricable link between the ion hydration structure and the pore steric effect and further find that ionic transmembrane transport can be regulated by breaking the balance between the hydrogen bond network (i.e., water-water) and ion hydration (i.e., ion-water) interactions of hydrated ion. For strongly hydrated (H2O)nCl- with more intense ion-water interactions, a higher salt concentration and coexisting ion competition led to a larger hydrated size and, thus, a higher ion rejection by the NF membrane, whereas weakly hydrated (H2O)nNO3- takes the reverse under the same conditions. Stronger OH--anion hydration competition resulted in a smaller hydrated size of (H2O)nCl- and (H2O)nNO3-, showing a lower observed average hydration number at pH 10.5. This study deepens the long-overlooked understanding of NF separation mechanisms, concerning the hydration structure.

Strategic Buried Defect Passivation of Perovskite Emitting Layers by Guanidinium Chloride for High-Performance Pure Blue Perovskite Light Emitting Diodes.

Perovskite light-emitting diodes (PeLEDs) show promise for high-definition displays due to their exceptional electroluminescent properties. However, the performance of pure blue PeLEDs is hindered by the unfavorable ionic behavior of halides and the presence of defective antisites in blue-emitting perovskite materials. An unstable buried interface between charge transport layers and the perovskite emitting layer is a major issue that limits carrier transport and recombination behavior in PeLEDs. In this study, effective buried defect passivation of pure blue perovskite emitting layers by introducing guanidinium chloride (GACl) as a bottom-passivating layer is demonstrated. The GACl bottom layer not only passivates the point defects present at the buried interface but also provides chloride anions to suppress ion migration and halide vacancy formation. Along with the defect passivation, GACl also enforces phase purity of 2D layered structure in the perovskite emitting layers to improve crystallinity and optoelectronic properties. As a result, the PeLEDs with high brightness (1200cd m-2) and excellent external quantum efficiency (6.61%) are achieved at a spectrally stable pure blue electroluminescence at 471nm (band width = 17.63nm). This study offers insights into the straightforward way for effective buried passivation for preparing high-performance PeLEDs.

Ionic Transport Behavior of Soft Nanochannels for Newtonian and Non-Newtonian Electrolytes

Ionic Transport Behavior of Soft Nanochannels for Newtonian and Non-Newtonian Electrolytes