Recently, the development of durable anion-exchange membrane fuel cells (AEMFCs) has increased in intensity due to their potential to use low-cost, sustainable components. However, the decomposition of the quaternary ammonium (QA) cationic groups in the anion-exchange membranes (AEMs) during cell operation is still a major challenge. Many different QA types and functionalized polymers have been proposed that achieve high AEM stabilities in strongly alkaline aqueous solutions. We previously developed an technique to measure AEM alkaline stabilities in an environment that simulates the low-hydration conditions in an operating AEMFC. However, this method required the AEMs to be soluble in DMSO solvent, so decomposition could be monitored using H nuclear magnetic resonance (NMR). We now report the extension of this protocol to spectroscopically measure the alkaline stability of insoluble AEMs. The stability ofradiation-grafted (RG) poly(ethylene--tetrafluoroethylene)-(ETFE)-based poly(vinylbenzyltrimethylammonium) (ETFE-TMA) and poly(vinylbenzyltriethylammonium) (ETFE-TEA) AEMs were studied using Raman spectroscopy alongside changes in their true OH conductivities and ion-exchange capacities (IEC). A crosslinked polymer made from poly(styrene--vinylbenzyl chloride) random copolymer and ,,','-tetraethyl-1,3-propanediamine (TEPDA) was also studied. The results are consistent with our previous studies based on QA-type model small molecules and soluble poly(2,6-dimethylphenylene oxide) (PPO) polymers. Our work presents a reliable technique to measure the true alkaline stability of AEMs for fuel cells and water electrolyzers.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10016746 | PMC |
http://dx.doi.org/10.1021/acsaem.2c03689 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Donghua University, No.2999, North Renmin Road, Songjiang District, Shanghai, CHINA.
Herein, we demonstrate a two-in-one strategy for efficient neutral electrosynthesis of H2O2 via two-electron oxygen reduction reaction (2e-ORR), achieved by synergistically fine-modulating both the local microenvironment and electronic structure of indium (In) single atom (SA) sites. Through a series of finite elemental simulations and experimental analysis, we highlight the significant impact of phosphorous (P) doping on an optimized 2D mesoporous carbon carrier, which fosters a favorable microenvironment by improving the mass transfer and O2 enrichment, subsequently leading to an increased local pH levels. Consequently, an outstanding 2e-ORR performance is observed in neutral electrolytes, achieving over 95% selectivity for H2O2 across a broad voltage range of 0.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Biopharmacy, School of Pharmaceutical Sciences, Jilin University, Changchun, People's Republic of China.
Physiol Plant
January 2025
College of Geography and Environment, Shandong Normal University, Jinan, China.
Climate change has exacerbated precipitation variability, profoundly impacting vegetation dynamics and community structures in arid ecosystems. There remains a notable knowledge gap regarding the ecological effects of altered precipitation on crassulacean acid metabolism (CAM) plants and their interactions with other photosynthetic types. This study investigated the response of the typical obligate CAM plant Orostachys fimbriata to extended watering intervals (WI4-WI8) and various competitive patterns (M-M) with the C grass Melilotus officinalis and the C grass Setaria viridis through greenhouse experiments.
View Article and Find Full Text PDFSci Rep
January 2025
Hangzhou Yanqu Information Technology Co., Ltd., Hangzhou, 310003, Zhejiang, China.
Electrocatalytic materials with dual functions of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) have received increasing attention in the field of zinc-air batteries (ZABs) research. In this study, bifunctional CoNC@NCXS catalysts were prepared by anchoring Co and N co-doped CoNC on N-doped carbon xerogel sphere (NCXS) based on the spatially confined domain effect and in-situ doping technique. CoNC@NCXS exhibited excellent ORR/OER activity in alkaline electrolytes with the ORR onset potential of 0.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Laboratory for Structural Engineering and Sustainable Catalysis, Department of Chemistry, University of North Bengal, Darjeeling 734013, India.
The upsurging of cost-effective electrocatalysts through the operando electro-oxidation approaches holds great promise for the scalable production of green energy in the pursuit of energy sustainability. This work introduces an operando electro-oxidation reconstitution strategy in producing a smart electrocatalyst, cobalt "oxyhydroxide" derived from a newly designed 2D cobalt(II) metal-organic framework (-) directly grown on nickel foam (NF), . The electrocatalyst, , exhibits an outstanding overpotential of 76 mV for the hydrogen evolution reaction and 336 mV for the oxygen evolution reaction to achieve a current density of 10 mA/cm with remarkable Faradaic efficiencies of 97.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!