Architecting the metal-nonmetal oxide layers for boosting the oxygen-evolving intrinsic activity of amorphous alloy

Designing high-efficiency and freestanding electrocatalysts hold immense importance in addressing the limitations of powdered electrocatalysts and accelerating the sluggish kinetics of the oxygen evolution reaction (OER) in advancing energy technologies. While dealloyed amorphous ribbons have been shown to be active and self-supporting electrocatalysts toward OER, the underlying enhancement mechanism remains unclear. Here, we developed a dealloyed Ni-Fe-B-Si-P amorphous electrocatalysts with a mixed oxide layer (including oxo-anions: phosphate, silicate, and borate). The dealloyed oxide layer optimizes the surface properties and chemical local environment of the amorphous ribbon, then shortens the multistep evolution path (Ni0 → Ni2+ → Ni3+ → Ni4+) toward Ni4+ species during the surface reconstruction process and decreased energy barriers for the dealloyed Ni-Fe-B-Si-P electrocatalyst during OER. Benefiting from the changes, the dealloyed Ni-Fe-B-Si-P enables a 56-fold increase in current density (at overpotential: 320 mV) and an 8-fold increase in turnover frequency values compared to undealloyed Ni-Fe-B-Si-P, demonstrating the major effect of the intrinsic activity on the OER performance of the dealloyed ribbon. This work sheds light on the enhancement mechanism of amorphous bulk electrocatalysts and offers valuable insights into the rational design of amorphous components and surface treatment processes.