Electrochemical amorphous-to-1T-phase reconfiguration of Ru-W bimetallic sulfide for sustainable hydrogen evolution

Abstract

Electrochemical reconfiguration of amorphous metallic materials offers exceptional opportunities for catalyst design. Here, we demonstrate a distinctive reconfiguration route toward highly active crystalline 1T-phase in amorphous Ru-W bimetallic sulfide. A micellar film-mediated strategy is developed to facilely fabricate large-area mesoporous films of the amorphous composite, involving sequential accumulation and association of Ru3+ and WS42- precursors through hierarchical “pyridyl–Ru3+–WS42-” coordination, followed by crystallization-retarding pyrolysis. The resulting catalyst reveals appealing hydrogen evolution performance, with a low initial overpotential of 11 mV at 10 mA cm-2 and high sustainability at 1.0 A cm-2 over 1600 h. Notably, sustained electrochemical stimuli triggers an distinctive amorphous-to-crystalline reconfiguration, gradually generating crystalline Ru-W bimetallic sulfide with a metastable 1T-phase. This substantially endows the catalyst with a remarkable long-term stability while further enhancing the catalytic activity (overpotential of merely 4 mV at 10 mA cm-2). Theoretical calculations reveal a unique electrochemical-dependent structural reorganization process, where external electron injection triggers charge redistribution that drives the atomic rearrangement, while the sulfur-bridged structure promotes efficient cooperative charge transfer and ensures the structural robustness of the metastable 1T-phase during the reconfiguration.