Dual Active Site Engineering in Porous NiW Bimetallic Alloys for Enhanced Alkaline Hydrogen Evolution Reaction
Weijie Li, Zhenrui Ni, Ouardia Akdim, Tao Liu, Bicheng Zhu, Panyong Kuang, Jiaguo Yu
Abstract
Abstract Utilizing dual active sites in electrocatalysts creates a synergistic effect, enabling the independent optimization of H 2 O dissociation and intermediate adsorption/desorption, which in turn enhances the efficiency of the hydrogen evolution reaction (HER). Herein, a porous NiW bimetallic alloy electrocatalyst using a dynamic H 2 bubble template (DHBT) strategy is fabricated. This electrocatalyst capitalizes on the synergistic effect of dual active sites, achieving industrial‐level current densities of 500 and 1000 mA cm −2 for HER in 1.0 M KOH, with low overpotentials of 198 and 264 mV, respectively. It also demonstrates excellent stability over a 200 h test. Theoretical studies reveal that alloying Ni with W shifts the d‐band center ( ε d ) of the W 5d orbital downward, which enhances *OH intermediate desorption and promotes H 2 O adsorption and dissociation at the W site, leading to increased active site availability. Meanwhile, this shift provides more accessible H* intermediates, further enhancing H 2 production at the Ni 2 W 1 hollow site. When the porous NiW bimetallic alloy electrocatalyst is implemented in a solar‐driven water splitting system, it achieves a high solar‐to‐hydrogen (STH) conversion efficiency of 16.59%. This work underscores the effectiveness of dual active site electrocatalysts for sustainable H 2 production.