Electronic Redistribution: Construction and Modulation of Interface Engineering on CoP for Enhancing Overall Water Splitting

TLDR

Interface engineering is an effective strategy to boost catalytic activity for water splitting. A hybrid V‑CoP@a‑CeO₂ nanoarray on carbon cloth enhances electron density at Co sites and lowers water adsorption energies, accelerating alkaline water‑splitting kinetics. The V‑CoP@a‑CeO₂ catalyst delivers high HER and OER activity, enabling a two‑electrode electrolyzer to reach 10 mA cm⁻² at 1.56 V and 100 mA cm⁻² at 1.71 V, demonstrating a promising design for efficient water electrolysis.

Abstract

Abstract Modulating and constructing interface engineering is an efficient strategy to enhance catalytic activity for water splitting. Herein, a hybrid nanoarray structure of V‐CoP@a‐CeO 2 , where “a” represents amorphous, integrated into carbon cloth is fabricated for water splitting. The synergy effect between V and CeO 2 can increase the electron density of Co atoms at active sites, further optimizing the Gibbs free energy of H* adsorption energy (Δ G H* ). Besides, V‐CoP@a‐CeO 2 possesses lower water adsorption/dissociation energies, enabling accelerated reaction kinetics in alkaline media. As expected, the V‐CoP@a‐CeO 2 exhibits superior performance toward the hydrogen evolution reaction and the oxygen evolution reaction. More importantly, a two‐electrode electrolyzer combined with an electrocatalyst of V‐CoP@ a‐CeO 2 only demands that voltages of electrolytic cell are 1.56 and 1.71 V to achieve the current densities of 10 and 100 mA cm −2 , respectively. This work provides guidance for the design or optimization of materials for water electrolysis and beyond.