Archipelago-like oxygen-vacancies-enriched amorphous-crystalline heterointerface for enhanced water splitting

Advancing the development of proficient bifunctional water splitting electrocatalysts and deciphering the underlying drivers of their performance are pivotal for accelerating the sustainable hydrogen energy sector. In this study, a novel Fe and P dual-doped cobalt molybdate electrocatalyst (P-FCMO@NF) is engineered in-situ on a nickel foam substrate that induces an archipelago-like amorphous-crystalline heterointerface as well as abundant oxygen vacancies (V_O) on the near-surface, in favor of the electron transport and enhancing the water splitting capability respectively. Consequently, P-FCMO@NF exhibits excellent electrocatalytic performance in 1 M KOH solution. The water splitting device shows an ultra-low work voltage of merely 1.55 V at a current density of 10 mA cm^-2 and demonstrates a long-term stability. The correlations between microstructural reconfiguration and sustainable electrocatalytic stability of P-FCMO@NF are deeply explored and verified. The work actually offers valuable insights that form a crucial foundation for the strategic design of innovative bifunctional electrocatalysts.