Search Results (452)

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes typically suffer from limited ionic conductivity at near-room temperature and often require inorganic reinforcement. Halide solid-state electrolytes such as Li₃InCl₆ (LIC) offer fast Li⁺ transport but are moisture-sensitive and typically require pressure-assisted densification. Here, we fabricate a flexible LIC–PEO composite electrolyte via slurry casting in acetonitrile with a small amount of LiPF₆ additive. The free-standing membrane delivers an ionic conductivity of 1.19 mS cm⁻¹ at 35 °C and an electrochemical stability window up to 5.15 V. Compared with pristine LIC, the composite shows improved moisture tolerance, and its conductivity can be recovered by mild heating after exposure. The electrolyte enables stable Li|LIC–PEO|Li cycling for >620 h and supports Li|LIC–PEO|NCM111 cells with capacity retentions of 84.2% after 300 cycles at 0.2 C and 80.6% after 150 cycles at 1.2 C (35 °C). Structural and surface analyses (XRD, SEM/EDX, XPS) elucidate the composite microstructure and interfacial chemistry. Full article

Countries like Saudi Arabia receive abundant sunshine with exceptionally high solar irradiance. High temperatures in desert regions and the sunray angle dependence of solar modules are some of the key challenges of conventional solar cells. Dye-sensitized solar cells present a compelling alternative with the simple cell design and use of non-toxic materials without angle dependence, but their performance hinges on the solid redox mediators used for dye regeneration. These mediators must have an electrical conductivity (σ_25°C) of more than 10⁻⁴ S cm⁻¹ with an activation energy of less than 0.3 eV for device application. Our work focused on novel solid Co(II/III) redox mediators using cobalt complexes and LiClO₄ in different matrices: pure PEO (an abbreviation for poly(ethylene oxide) with its redox mediator as M1), a [PEO–SN] blend (M2A and M2B with ethylene oxide to lithium ions molar ratio of 112.9 and 225.8, respectively), and pure SN (an abbreviation for succinonitrile with its redox mediator as M3). Impedance spectroscopy was the key technique, showing M1 and M2 behave like a mediator explainable with an (R₁–C)-type circuit, while M3 is explainable with an (R₁ − [R₂‖C])-type circuit. M3 achieved the highest value of σ_25°C with 2 × 10⁻³ S cm⁻¹, while M1 had the lowest σ_25°C, 3 × 10⁻⁵ S cm⁻¹. M2 achieved an optimal balance with σ_25°C of 4 × 10⁻⁴ S cm⁻¹ (M2A) and 1.5 × 10⁻⁴ S cm⁻¹ (M2B). M2 exhibited a remarkably low pseudo-activation energy of 0.042 eV and a Vogel–Tammann–Fulcher behavior ideal for consistent performance across temperatures. In contrast, M1 and M3 showed higher Arrhenius-type activation energies (>0.74 eV) in their solid states. These results correlated with those of the XRD, FT-IR spectroscopy, XPS, SEM, DSC, and TGA analyses. Ultimately, the [PEO–SN] blend emerges as a robust matrix, enabling the combination of high conductivity and low activation energy needed for a durable device in harsh environments. Full article

Silicon is widely recognized as a next-generation anode owing to its exceptional theoretical capacity, yet its practical deployment in lithium-ion batteries is constrained by severe volume expansion, particle fracture, loss of electrical percolation, and solid electrolyte interphase layer instability. Polymer-based strategies have emerged as accessible solutions to engineer extensive volume changes and interfacial compatibility, while preserving pathways for charge transport. Viscoelastic polymer binders dissipate stress, catechol-inspired chemistries strengthen adhesion and tailor interphases, and conductive polymers can function simultaneously as binder, electronic additive, and artificial SEI. This review describes these approaches through a structure–process–performance perspective, emphasizing practically relevant metrics, such as initial capacity, initial Coulombic efficiency, and long-term cycling stability. We organize the main section into (i) dopamine-derived interfacial engineering, (ii) self-healing three-dimensional network binders, and (iii) conductive-polymer-based designs. In the last section, we articulate the functional requirements of polymers in silicon anodes, outline the ideal structural designs, and provide forward-looking avenues for future lithium-ion battery anode research. Full article

Organic electrochemical transistors (OECTs) are compelling artificial synapses because mixed ionic–electronic coupling and transport enables low-voltage, analog weight updates that mirror biological plasticity. Here, we engineered solid-state, polymer electrolyte-gated vertical OECTs (vOECTs) and elucidate how electrolyte molecular weight influences synaptic dynamics. Using Pg2T-T as the redox-active channel and pDADMAC polymer electrolytes spanning low- (~100 k), medium- (~300 k), and high- (~500 k) molecular weights, cyclic voltammetry reveals reversible Pg2T-T redox, while peak separation and current density systematically track ion transport kinetics. Increasing electrolyte molecular weight enlarges the transfer curve hysteresis (memory window ΔV_mem from ~0.15 V to ~0.50 V) but suppresses on-current, consistent with slower, more confining ion motion and stabilized partially doped states. Devices exhibit rich short- and long-term plasticity: paired-pulse facilitation (A₂/A₁ ≈ 1.75 at Δt = 50 ms), frequency-dependent EPSCs (low-pass accumulation), cumulative potentiation, and reversible LTP/LTD. A device-aware CrossSim framework built from continuous write/erase cycles (probabilistic LUT) supports Fashion-MNIST inference with high accuracy and bounded update errors (mean −0.02; asymmetry 0.198), validating that measured nonidealities remain algorithm-compatible. These results provide a materials-level handle on polymer–ion coupling to deterministically tailor temporal learning in compact, robust neuromorphic hardware. Full article

Accurate potentiometric sensing critically depends on the stability and reproducibility of the reference electrode potential. Conventional liquid-filled Ag/AgCl or calomel electrodes, though well-established, are poorly compatible with miniaturized, portable, or long-term in situ sensing devices due to electrolyte leakage, junction potential instability, and maintenance requirements. Recent advances in solid-state and membrane-based reference electrodes offer a promising alternative by eliminating the liquid junction while maintaining stable and well-defined potential. This review summarizes the advancements in polymer-based and composite reference membranes, focusing on material strategies, stabilization mechanisms, and integration approaches. Emphasis is placed on ionic-liquid-doped membranes, conducting polymers, lipophilic salts, and carbon nanomaterials as functional components enhancing interfacial stability and charge transfer. The performances of various architectures, solid-contact, liquid-junction-free, and quasi-reference systems, are compared in terms of potential drift, matrix resistance, biocompatibility, and manufacturability. Furthermore, recent developments in printed, microfluidic, and wearable potentiometric platforms demonstrate how reference membrane innovations enable reliable operation in compact, low-cost, and flexible analytical systems. The review outlines current trends, challenges, and future directions toward universal, miniaturized, and leak-free reference electrodes suitable for innovative sensing technologies. Full article

Solid-state batteries (SSBs) are regarded as one of the most promising next-generation energy storage technologies due to their high energy density and improved safety. To achieve this goal, the development of solid-state electrolytes with high ionic conductivity and low interfacial resistance is essential. In recent years, composite polymer electrolytes (CPEs) have garnered extensive attention due to their ability to combine the intrinsic flexibility of polymers with the enhanced ionic conductivity and mechanical robustness provided by inorganic fillers. Metal–organic frameworks (MOFs), characterized by tunable pore structures, high surface areas, and excellent thermal and mechanical stability, are considered ideal fillers for constructing MOF–polymer composite electrolytes (MPCEs). This review summarizes the performance enhancement mechanisms of MPCEs and strategies for electrode–electrolyte interface stability. First, the primary preparation methods of MPCEs are introduced. Subsequently, the roles of MOFs in regulating ionic transport, suppressing dendrite growth, improving electrochemical stability, and optimizing the solid electrolyte interphase (SEI) layer are discussed. In addition, various interface engineering strategies are highlighted, including in situ polymerization of the polymer matrix, in situ growth of MOF fillers, integration of liquid plasticizers forming gel-like ionic conductor, and design of composite electrode to enhance interfacial compatibility and stability. Finally, the significant challenges and future research directions of MPCEs are outlined. This review provides valuable insights into the rational design of MPCEs and offers guidance for the development and practical application of high-performance SSBs. Full article

MXene–polymer hybrids combine the high in-plane conductivity and rich surface chemistry of MXenes with the processability and mechanical tunability of polymers for lithium-metal and lithium–sulfur batteries. Most reported systems still rely on HF-etched MXenes, introducing F-rich terminations, safety and waste issues, and poorly controlled surfaces. This review instead centers on fluoride-free synthesis routes, benchmarks them against HF methods, and translates route–termination relationships into practical rules for choosing polymer backbones. We track the evolution from early linear hosts such as PEO- and PVDF-type polymers to polar nitrile or carbonyl matrices, crosslinked and ionogel networks, and emerging biopolymers and COF-type porous frameworks that are co-designed with MXene terminations to regulate ion transport, interfacial chemistry, and mechanical robustness. These chemistry–backbone pairings are linked to five scalable fabrication modes, including solution blending and film casting, in situ polymerization, surface grafting, layer-by-layer assembly, and electrospinning, and to roles as solid or quasi-solid electrolytes, artificial interphases, separator-like coatings, and electrode-facing architectures. Finally, we highlight key evidence gaps and reporting standards needed to de-risk scale-up of green MXene–polymer batteries. Full article

Composite electrolytes for applications in batteries and supercapacitors, i.e., in electrochemical energy technology, are gaining growing attention. In the absence of a commonly accepted definition, binary and ternary combinations of materials, e.g., a polymer with an electrolyte salt or electrolyte salt solution and a third conductivity- and performance-enhancing constituent, are assumed as a definition of a composite electrolyte in the following review. Relevant fundamentals and reported research results, including explanations of the described effects of added ingredients and achieved improvements, are reviewed. Future perspectives and directions of further research are sketched. Full article

This comprehensive review examines the transformative role of metal–organic frameworks (MOFs) in advancing battery separator technology to address critical safety challenges in rechargeable lithium metal batteries. MOF-based separators leverage their highly specific surface area, tunable pore structures, and functionalized organic ligands to enable precise ion-sieving effects, uniform lithium-ion flux regulation, and dendrite suppression—significantly mitigating risks of internal short circuits and thermal runaway. We systematically analyze the mechanisms by which classical MOF families (e.g., ZIF, UiO, MIL series) enhance separator performance through physicochemical properties such as electrolyte wettability, thermal stability (>400 °C), and mechanical robustness. Furthermore, we highlight innovative composite strategies integrating MOFs with polymer matrices (e.g., PVDF, PAN) or traditional separators, which synergistically improve ionic conductivity while inhibiting polysulfide shuttling in lithium–sulfur batteries and side reactions in aqueous zinc-ion systems. Case studies demonstrate that functionalized MOF separators achieve exceptional electrochemical outcomes: Li–S batteries maintain >99% Coulombic efficiency over 500 cycles, while solid-state batteries exhibit 2400 h dendrite-free operation. Despite promising results, scalability challenges related to MOF synthesis costs and long-term stability under operational conditions require further research. This review underscores MOFs’ potential as multifunctional separator materials to enable safer, high-energy-density batteries and provides strategic insights for future material design. Full article

Methodological fusion of materials chemistry, which enables us to create materials, with nanotechnology, which enables us to control nanostructures, could enable us to create advanced functional materials with well controlled nanostructures. Positioned as a post-nanotechnology concept, nanoarchitectonics will enable this purpose. This review paper highlights the broad scope of applications of the new concept of nanoarchitectonics, selecting and discussing recent papers that contain the term ‘nanoarchitectonics’ in their titles. Topics include controls of dopant atoms in solid electrolytes, transforming the framework of carbon materials, single-atom catalysts, nanorobots and microrobots, functional nanoparticles, nanotubular materials, 2D-organic nanosheets and MXene nanosheets, nanosheet assemblies, nitrogen-doped carbon, nanoporous and mesoporous materials, nanozymes, polymeric materials, covalent organic frameworks, vesicle structures from synthetic polymers, chirality- and topology-controlled structures, chiral helices, Langmuir monolayers, LB films, LbL assembly, nanocellulose, DNA, peptides bacterial cell components, biomimetic nanoparticles, lipid membranes of protocells, organization of living cells, and the encapsulation of living cells with exogenous substances. Not limited to these examples selected in this review article, the concept of nanoarchitectonics is applicable to diverse materials systems. Nanoarchitectonics represents a conceptual framework for creating materials at all levels and can be likened to a method for everything in materials science. Developing technology that can universally create materials with unexpected functions could represent the final frontier of materials science. Nanoarchitectonics will play a significant part in achieving this final frontier in materials science. Full article

Metal anodes promise improvements in energy density and cost; however, their performance is determined within the first several nanometers at the interface. This review reports on how polymer-based artificial solid electrolyte interphases (SEIs) are engineered to stabilize Li and aqueous-Zn anodes, and how these designs are now evaluated against operando readouts rather than post-mortem snapshots. We group the related molecular strategies into three classes: (i) side-chain/ionomer chemistry (salt-philic, fluorinated, zwitterionic) to increase cation selectivity and manage local solvation; (ii) dynamic or covalently cross-linked networks to absorb microcracks and maintain coverage during plating/stripping; and (iii) polymer–ceramic hybrids that balance modulus, wetting, and ionic transport characteristics. We then benchmark these choices against metal-specific constraints—high reductive potential and inactive Li accumulation for Li, and pH, water activity, corrosion, and hydrogen evolution reaction (HER) for Zn—showing why a universal preparation method is unlikely. A central element is a system of design parameters and operando metrics that links material parameters to readouts collected under bias, including the nucleation overpotential (η_nuc), interfacial impedance (charge transfer resistance (R_ct)/SEI resistance (R_SEI)), morphology/roughness statistics from liquid-cell or cryogenic electron microscopy (Cryo-EM), stack swelling, and (for Li) inactive-Li inventory. By contrast, planar plating/stripping and HER suppression are primary success metrics for Zn. Finally, we outline parameters affecting these systems, including the use of lean electrolytes, the N/P ratio, high areal capacity/current density, and pouch-cell pressure uniformity, and discuss closed-loop workflows that couple molecular design with multimodal operando diagnostics. In this view, polymer artificial SEIs evolve from curated “recipes” into predictive, transferable interfaces, paving a path from coin-cell to prototype-level Li- and Zn-metal batteries. Full article

Solid polymer and composite polymer electrolytes have been investigated as a replacement for liquid electrolytes in lithium batteries and have shown promising conductivities at room temperature. However, the literature reports often do not fully investigate the effects of residual solvent or testing apparatus conditions, leading to discrepancies in reported performance and possible conflation of conductivity values. Using combinations of poly (vinylidene fluoride-co-hexafluoropropylene), succinonitrile, and lithium lanthanum zirconium tantalum oxide, this work aims to develop an understanding of how polymer electrolyte composition, including solvent retention, affects conductivity. A custom-designed controllable pressure test fixture was utilized to determine ionic conductivity of the composite polymer electrolyte films at a wide range of pressures (1.5–18.7 psi) and temperatures 10–90 °C. Applied pressure during testing greatly influences apparent conductivities, with optimal composite film conductivity values ranging from 1.2 × 10⁻⁵ to 4.1 × 10⁻⁵ S cm⁻¹ at room temperature. At elevated temperatures, the composite films achieved greater than 1 mS cm⁻¹. The ideal pressure was found to be dependent on the polymer electrolyte additives. Symmetric cell testing showed over 99% Coulombic efficiency for over one hundred cycles at 0.1 mA cm⁻². The results of this work highlight the importance of careful characterization of electrolyte films and controlled test fixture pressure when developing polymer electrolytes. Full article

Lithium-ion batteries, widely used in phones and electric vehicles, pose safety concerns due to the flammability of conventional liquid electrolytes, which are prone to ignition under elevated temperatures and mechanical stress, increasing the risk of fire. Polymer electrolytes have been employed as a safer solution thanks to their superior thermal stability and mechanical strength. However, despite these advantages, many polymer matrices pose a fire hazard, limiting their potential. This review assesses recent advances in enhancing the flame retardancy of polymer electrolytes through a variety of strategies, namely the incorporation of flame-retardant additives, the addition of nanoscale fillers to improve thermal resistance, and the design of layered or hybrid polymer membrane structures that function as thermal barriers. This review evaluates the effectiveness of these methods, examining their flame-retardancy as well as their influences on ionic conductivity and overall battery performance. By highlighting recent progress and enduring safety challenges in solid-state batteries, it aims to offer insights for developing lithium batteries with enhanced safety and high performance. Full article

Polymer materials have become promising candidates for next-generation energy storage, with structural tunability, multifunctionality, and compatibility with a variety of device platforms. They have a molecular design capable of customizing ion and electron transport routes, integrating redox-active species, and enhancing interfacial stability, surpassing the drawbacks of traditional inorganic systems. New developments have been made in multifunctional polymers that have the ability to combine conductivity, mechanical properties, thermal stability, and self-healing into a single scaffold system, which is useful in battery, supercapacitor, and solid-state applications. By incorporating polymers with carbon nanostructures, ceramics, or two-dimensional materials, hybrid polymer nanocomposites improve electrochemical performance, durability, and mechanical compliance, and the solid polymer electrolytes, as well as artificial solid electrolyte interphases, resolve dendrite growth and safety issues. The multifunctionality also extends to flexibility, stretchability, and miniaturization, which implies that polymers are suitable for use in wearable devices and biomedical devices. At the same time, sustainable polymer innovation focuses on bio-based feedstocks, which can be recycled, and green synthesis pathways. Polymer discovery using artificial intelligence and machine learning is faster than standard methods, predicts structure–property–performance relationships, and can be rationally engineered. Although there are difficulties in stability during long periods, scalability, and trade-offs between indeedness and mechanical endurance, polymers are a promising avenue with regard to dependable, safe, and sustainable power storage. This review presents the molecular strategies, multifunctional uses, and prospects, where polymers are at the center of the next-generation energy technologies. Full article

Aqueous zinc-ion batteries (ZIBs) have attracted growing interest as promising candidates for large-scale and flexible energy storage due to their intrinsic safety, low cost, and environmental sustainability. However, several persistent issues—such as uncontrolled Zn dendrite growth, hydrogen evolution-induced anode corrosion, and cathode dissolution—continue to hinder their commercial deployment. To address these challenges, hydrogel polymer electrolytes (HPEs) have emerged as an effective strategy. Their unique three-dimensional polymer networks not only retain water and confine ion transport, but also provide a solid–liquid hybrid environment that enhances ionic conductivity and interfacial compatibility. These features enable HPEs to suppress side reactions and improve both electrochemical stability and mechanical adaptability, which are especially valuable for flexible ZIB devices. This review first summarizes fundamental energy storage mechanisms in aqueous ZIBs, including reversible Zn²⁺ insertion/extraction, proton co-insertion, and cathode phase evolution. It then highlights recent progress in HPE design, with emphasis on polyacrylamide (PAM), polyvinyl alcohol (PVA), and polyacrylic acid (PAA)-based systems, with strategies for dendrite suppression, interfacial regulation, and mechanical robustness. Finally, current challenges and future directions are discussed, with a forward-looking perspective on scalable fabrication methods, advanced electrolyte design, and deeper mechanistic understanding necessary to fully realize the potential of HPE-enabled aqueous ZIBs. Full article