Transition metal

Physics

Engineering

Oxygen evolution

Physical chemistry

Current (fluid)

Embedded system

Catalysis

Electrode

Inorganic chemistry

Chemistry

Overpotential

Metallurgy

Materials science

Current density

Bifunctional

Bottleneck

Water splitting

Computer science

Chemical engineering

Electrochemistry

Metal

Biochemistry

Quantum mechanics

Alkaline earth metal

Photocatalysis

Thermodynamics

Journal of Material Science and Technology

Earth-abundant electrocatalysts for large-current-density water splitting under alkaline condition are desirable. Oxygen evolution reaction, which is a bottleneck of the overall water splitting, faces the problems of complicated reconstruction and deficiency in rational design of active sites. Herein, we report a series of transition metal chalcogenides for alkaline OER. Among them, FeCoNi(S) displayed a low overpotential of 293 mV to deliver a current density of 500 mA cm−2, which is in the top level of non-precious metal based OER electrocatalysts. A combination of (ex) in situ characterizations and DFT calculation shows that Ni(Fe,Co) trimetallic oxyhydroxides were the active sites for highly-efficient OER. Furthermore, for FeCoNi(S), when used as a bifunctional catalyst for water splitting, it only required a cell voltage of 1.84 V to deliver ∼500 mA cm−2 with extraordinary long-term stability over 2000 h. This work provides the comprehension of high-efficiency, robust catalysts for OER and overall water splitting at large current densities in alkaline media.

Trimetallic oxyhydroxides as active sites for large-current-density alkaline oxygen evolution and overall water splitting