FeSe2-CoSe2/CoSe(2 )yolk-shell nanoboxes as superior electrocatalysts for the oxygen evolution reaction

Abstract

Exploring high-efficiency electrocatalysts and hollow nanostructures have attracted research interest for the water-splitting process. FeSe2-CoSe2/CoSe2 yolk-shell nanobox (YBs) was synthesized via a MOF-based selftemplating approach for OER in alkaline solutions. First, ZIF-67 nanocubes were converted to ZIF-67/CoFe-PBA YBs by ion exchange. After subsequent selenization, the derived FeSe2-CoSe2/CoSe2 YBs exhibited high OER activity (260 mV at 10 mA cm(-2)), excellent stability (over 20 h), and remarkably outperformed the commercial RuO2. The large surface area, abundant active sites, high electric conductivity and synergistic effect of heterostructure interfaces are responsible for significantly improving efficiency and stability.