Hollow CoNiFe ternary metal selenide electrocatalysts derived from Prussian blue analogues for boosting the oxygen evolution reaction

Abstract

The development of effective electrocatalysts is a top priority for the oxygen evolution reaction (OER), which is the crucial half-reaction of water electrolysis, since electrocatalytic water splitting for hydrogen production offers a practical solution to the upcoming energy crisis. Herein, we report a strategy to fabricate hollow ternary metal selenide (CoNiFe–Se) nanocubes derived from Prussian blue analogues (PBAs) by phytic acid etching and low-temperature gas-phase selenization. Due to the advantages of its multi-component composition and hollow structure, CoNiFe–Se exhibited a low overpotential of 275 mV@10 mA cm⁻², a small Tafel slope of 62.3 mV dec⁻¹ and a long-term stability of more than 80 h in 1.0 M KOH. This research offers an innovative idea and a straightforward technique for preparing hollow multimetallic selenide electrocatalysts derived from PBAs.