The development of cathodes with high sulfur loading is essential for practical high-energy lithium–sulfur batteries. The binder functions as a polymeric framework that integrates active materials and conductive agents, while preserving electrode integrity and influencing electrochemical behavior. In lithium–sulfur systems, binders with polar functional groups that interact strongly with lithium polysulfides are crucial to suppress the shuttle effect and enhance cycling stability. Here, we design a multifunctional binder, poly(amic acid)–dextrin copolymer (PDB), which incorporates amide, carboxyl, hydroxyl, and imide groups within a three-dimensional network. This architecture provides mechanical robustness, immobilizes polysulfides, accelerates redox kinetics, and improves interfacial contact among electrode components. As a result, lithium–sulfur cells with PDB deliver a specific capacity of 590 mAh g− 1 after 100 cycles at 0.5 C, and maintain 357 mAh g− 1 under a high sulfur loading of 9.0 mg cm− 2 after 100 cycles at 0.2 C. This work demonstrates that multifunctional binder systems play a pivotal role in advancing lithium–sulfur batteries toward scalable, high-performance, and cost-effective energy storage technologies.

For the first time, we report on the functionalization of graphene oxide (GO) with 4,4 '-methylenedianiline (MDA) and its subsequent quaternization with glycidyltrimethylammonium chloride (GTMAC) to produce quaternized GO (QGO). The synthesized QGO is used as a filler in quaternized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO) matrix to fabricate an anion exchange membrane for a fuel cell. The QPPO-QGO-0.5% membrane exhibits the highest ion exchange capacity (IEC) and hydroxide ion conductivity (HIC) of 3.10 meq/g and 139 mS/ cm, respectively. Additionally, it maintains the 93 % of alkaline stability after 1000 hrs, which is higher than that of pure QPPO and other QGO-mixed QPPO membranes. Furthermore, single H2/O2 fuel cell is fabricated using the QPPO-QGO-0.5 % composite membrane, which exhibits the maximum peak power density (MPPD) of 372 mW/cm2 at 0.54 V and a current density of 688 mA/cm2 which is also higher than the pure QPPO of 311 mW/ cm2. These results indicate an enhanced performance of fabricated composite membranes as an anion exchange membrane (AEM) for fuel cells, demonstrating their potential for future applications.

In vanadium redox flow batteries (VRFBs), vanadium ion crossover contributes to performance degradation and a reduced system lifespan. Polybenzimidazole (PBI) membranes have been proposed as an effective solution to minimize ion crossover. In this study, PBI was used to achieve low vanadium ion permeability, while the addition of 1-ethyl-3-methylimidazolium dicyanamide (EMIM-DCA) created microstructures in the polymer, increasing ion pathways. Furthermore, a 10 mu m thin PBI-EMIM-DCA 45 wt % (PED 45) membrane was fabricated to minimize membrane resistance. PED 45 exhibits a vanadium ion permeability of 1.4 x 10-8 cm2 min-1 and a proton selectivity of 34.2 x 107 mS min cm-3. This results in 71- and 22-fold lower permeability compared to Nafion N115 and Fumatech FAP-450 membranes, respectively, while providing 4- and 14-fold higher proton selectivity, respectively. PED 45 demonstrates a Coulombic efficiency (CE) of up to 99.6% and an energy efficiency (EE) of 77.8% at a current density of 100 mA cm-2. Its self-discharge (SD) times are 6-9 times longer than those of other membranes, and its long-term stability shows over 5% higher efficiency across 100 cycles. PED 45 has proven to be a high-performance membrane for VRFB applications.

Research on carbon dioxide free energy sources is increasing due to climate change, with green hydrogen gaining significant attention for its eco-friendly production process. This study focused on creating a diaphragm for alkaline water electrolysis using the TIPS method, utilizing the engineering thermoplastics PEEK and PPS for their excellent mechanical properties and heat resistance. DPK was employed as a diluent, and the phase diagram was established by measuring the crystallization temperature and cloud point based on polymer content. The morphology of the diaphragm, both surface and cross-section, was observed using an SEM, while tensile strength, alkaline stability, and permeability tests assessed its suitability for alkaline electrolysis conditions. The diaphragm with a polymer content of 20 wt% demonstrated a mechanical strength of 31.9 MPa, making it viable for operational use in alkaline electrolysis. All the diaphragms exhibited exceptional alkali resistance, with weight changes of less than 1 % in a 25 to 30 wt% KOH solution. Additionally, permeability tests indicated that permeability decreased as polymer content increased. Electrochemical evaluations revealed that the 20 wt% polymer content diaphragm achieved the best performance, delivering 188.7 mA/cm2. This study confirms the potential of using these diaphragms in efficient and sustainable alkaline water electrolysis systems.

Various industries, such as food, petrochemicals, and pharmaceuticals, have recognized the importance of separation technologies for large molecules such as dye. A thin polyamide layer is commonly used in thin film composite membranes for separation applications, but fabricating a polyamide selective layer on hollow fiber (HF) membranes remains challenging. This research focuses on producing polyamide-based HF membranes by circulating aqueous and organic solutions during interfacial polymerization. By varying the solution flow rate, the dye rejection performance was investigated concerning morphology, polyamide thickness, mechanical properties, and hydrophilicity. All generated membranes consistently rejected over 98% of congo red dye, with the highest rejection rate for methyl orange reaching approximately 92%. The most efficient membranes were produced with an aqueous solution flow rate of 180ml/min and an organic solution flow rate of 220ml/min. These membranes exhibited notable ethanol permeance, with rejection rates of 99.75% for congo red and 91.68% for methyl orange. Additionally, they show promise for application in reverse osmosis processes for salt removal.

A systematic comparison has been made of three different porous carbon structures derived from waste coffee grounds to investigate the effect of carbon porosity on the electrochemical performance of RT Na-S batteries. The differences in their electrochemical performances were investigated in relation to the pore size distribution and the presence of sulfur molecules (Sn, 2 & LE; n & LE; 8) in the pores. We demonstrated that the hierarchically porous structure resulted in good rate capability and superior cycling stability. In particular, optimized carbon with micro-, meso-, and macroporous structures is beneficial because of its excellent wettability and kinetic acces-sibility. The optimized carbon structure with an appropriate sulfur content exhibited significantly higher ca-pacity retention and long cycle stability in RT Na-S batteries. In addition, the reaction mechanisms have been investigated in combination with X-ray photoelectron spectroscopy measurements during the discharge process. The study established a relevance between the exact regulation of the pore structure of the carbon materials and their electrochemical performance, and also built a correlation between waste biomass and high-effective energy storage materials, which can inspire the rational design of porous carbon structures for further development of the highly efficient, cost-effective and sustainable RT Na-S batteries.

Shuttling of soluble polysulfides (Li2Sn, 4 <= n <= 8) results in a low discharge capacity and unstable cycling performance of lithium-sulfur (Li-S) batteries. Furthermore, the formation of insoluble sulfides (Li2S2/Li2S) can retard the reaction kinetics, resulting in poor rate capability and short cycle life. In this study, a novel structural configuration, including a honeycomb-like porous carbon (HPC) as the sulfur host and gel polymer electrolyte (GPE), is proposed. HPC derived from waste coffee grounds possesses a tri-modal pore system. The micropore, as the main reactor, undergoes a "solid-solid" reaction mechanism in carbonate -based electrolyte, effectively preventing the generation of polysulfides. The macro-and mesopores can improve the accessibility of the electrolyte, accelerating ion transfer in the cell. Density functional theory calculations reveal that the functional groups on the HPC show strong interactions with polysulfides. These data in combination with X-ray photoelectron spectroscopy measurements indicate the presence of ef-fective and stable mediator groups without the formation of polysulfides. The GPE provides adequate electrolyte infiltration and minimizes the leakage of flammable liquid, affording excellent cycling stability. As a result, the cell with this novel configurational shows only 0.03% capacity fading per cycle over 1500 cycles at 0.5 C-rate, providing excellent long-term cycle durability up to 10 C-rate. The excellent cycling stability and rate performance demonstrate that the novel structural configuration is effective in improving the electrochemical performance and prolonging the cycle life of Li-S batteries.(c) 2022 Elsevier B.V. All rights reserved.