Water electrolysis technologies for hydrogen production from renewable energy play an important role in a carbon-free energy scenario. Anion exchange membrane water electrolysis (AEMWE) is one of the most cost-effective and promising water electrolysis technologies due to the application of efficient, non-noble metal electrocatalysts and the fast development of anion exchange membranes (AEMs). In this review, the most recent and significant achievements in AEMWE were summarized, including the progress in enhancing AEM conductivity and understanding their degradation mechanism, and the hot topics concerning the electrocatalyst design. The key factors that affect AEMWE performance were pointed out, further challenges and opportunities have also been discussed. The expectations for future development of AEMWE devices were also addressed. Finally, this review provided valuable guidelines for developing highly active and durable electrocatalysts and advancing the fabrication of AEMWE devices.
The nitrogen doped carbon (NC) encapsulating metal particles (metal/NC) are promising low-cost bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries. However, the states of the art catalytic performance are still significantly restricted by the limited content of active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, a series of NC encapsulating CoNi samples as a bifunctional catalyst for both ORR and OER were synthesized via a simple pyrolysis method. Large surface area and high content M-Nx active sites promote the ORR activity and accelerate the surface reconstruction layer for high OER performance. The NC encapsulating CoNi with optimized Co/Ni ratio (2 : 1) shows high ORR activity with a half-wave of potential (0.85 V) and a low overpotential of 309 mV for OER. Rechargeable Zn-air battery assembled by an air cathode with the NC encapsulating CoNi exhibits a power density of 143 mW cm−2 and good cyclability over 100 h at 10 mA cm-2. This mechanism work provides a feasible strategy for developing high activity and low cost bifunctional oxygen electrocatalysts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.