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论文类型：期刊论文

发表时间：2020-02-01

发表刊物：ADVANCED ENERGY MATERIALS

收录刊物：EI、SCIE

卷号：10

期号：5

ISSN号：1614-6832

关键字：electrocatalysis; in situ transformation; vacancies; water oxidation

摘要：Electrocatalytic water splitting for hydrogen generation is hindered by the sluggish kinetics of water oxidation, and highly efficient electrocatalysts for the oxygen evolution reaction (OER) are urgently required. Numerous bi- and multimetal-based, low-cost, high-performance OER electrocatalysts have been developed. However, unary metal-based high-performance electrocatalysts are seldom reported. In the present study, Co-2(OH)(3)Cl/vanadium oxide (VOy) composites are synthesized, from which VOy is completely etched out by a simple cyclic voltammetry treatment, which simultaneously transforms Co-2(OH)(3)Cl in situ to ultrafine CoOOH. The selective removal of VOy modulates the nature of the surface in the obtained CoOOH by creating surface oxygen vacancies (V-o), along with disordered grain boundaries. The best-performing CoOOH with optimum V-o is found to be associated with a low overpotential of 282 mV at 10 mA cm(-2) catalytic current density on a simple glassy carbon electrode for OER. This facile protocol of selectively etching VOy to modulate the nature of the surface is successfully applied to synthesize another Fe-based electrocatalyst with high OER performance, thus establishing its utility for unary metal-based electrocatalyst synthesis.