Atomic Doping of Sr–Co–Ni on Tungsten Carbide Electrocatalyst for Synergistically Enhanced Water Splitting Performance

TL;DR

This paper introduces a new electrocatalyst with atomic doping that improves water splitting for hydrogen production.

Contribution

A novel strategy of atomically doping Sr, Co, and Ni onto tungsten carbide to enhance electrocatalytic performance.

Findings

Doping Sr with Co and Ni reduces the energy barrier for oxygen evolution (OER) to 300 mV.

Hydrogen evolution (HER) performance reaches 125 mV at 10 mA cm–2 with 60-hour stability.

Sr doping alters the electronic structure of Wx C, improving catalytic activity.

Abstract

Electrocatalysts play a pivotal role in the quest for
renewable
hydrogen energy via water electrolysis. This study presents a novel
approach to synthesizing atomically doped Sr, Co, and Ni atoms onto
tungsten carbide (W
x
C) via van der Waals
interactions. Through systematic first-principles calculations, we
investigate the intricate interplay of s–d orbital coupling
among Sr, Co, and Ni atoms, revealing their profound impact on the
electronic structure of W
x
C. This reveals
that the addition of Sr to Co and Ni atoms decreases the absorption
energy of the intermediate, which enhances catalytic activity at the
Co and Ni sites. It demonstrates the strategy of ultralow loading
of Sr atoms onto nonprecious transition metals, reducing the energy
barrier for the OER (overpotential of 300 mV) and enhancing HER performance
(125 mV at 10 mA cm–2), with stability maintained
for 60 h. These findings underscore the potential of atomically engineered
electrocatalysts in advancing sustainable hydrogen production.

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