Daojin Zhou, Jiaqi Yu, Jialun Tang, Xiao-Yan Li, Pengfei Ou
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引用次数: 0
Abstract
Cobalt (Co)-based oxides show promising activity as precious metal-free catalysts for the oxygen evolution reaction in proton exchange membrane water electrolysis, but the dissolution of Co has limited the durability of Co3O4 at industrially relevant current densities. This work demonstrates that cation in an octahedral coordination environment accounts for the oxygen evolution activity. Using a mixed inverse-normal phase spinel CoxGa(3-x)O4 as a proof-of-concept example, the designed Co2+-O-Co3+ motifs in octahedral sites trigger oxygen evolution through a kinetically favorable radical coupling pathway. Furthermore, lattice oxygen exchange, a leading factor in catalyst structural degradation for normal Co3O4, is suppressed, as evidenced by isotopic labeling experiments and theoretical calculations. With the optimized catalyst, Co1.8Ga1.2O4, an overpotential of 310 mV at 10 mA cm−2 is reported, with stable operation at 200 mA cm−2 for 200 h in a three-electrode setup, and a proton exchange membrane electrolyzer operating at 200 mA cm−2 for 450 h.
期刊介绍:
Established in 2011, Advanced Energy Materials is an international, interdisciplinary, English-language journal that focuses on materials used in energy harvesting, conversion, and storage. It is regarded as a top-quality journal alongside Advanced Materials, Advanced Functional Materials, and Small.
With a 2022 Impact Factor of 27.8, Advanced Energy Materials is considered a prime source for the best energy-related research. The journal covers a wide range of topics in energy-related research, including organic and inorganic photovoltaics, batteries and supercapacitors, fuel cells, hydrogen generation and storage, thermoelectrics, water splitting and photocatalysis, solar fuels and thermosolar power, magnetocalorics, and piezoelectronics.
The readership of Advanced Energy Materials includes materials scientists, chemists, physicists, and engineers in both academia and industry. The journal is indexed in various databases and collections, such as Advanced Technologies & Aerospace Database, FIZ Karlsruhe, INSPEC (IET), Science Citation Index Expanded, Technology Collection, and Web of Science, among others.