Enhanced water‐splitting performance: Interface‐engineered tri‐metal phosphides with carbon dots modification

Abstract Designing integrated overall water‐splitting catalysts that maintain high efficiency and stability under various conditions is an important trend for future development, yet it remains a significant challenge. Herein, novel nanoflower‐like tri‐metallic Ni–Ru–Mo phosphide catalyst ((Ni–Ru–Mo)P@F‐CDs), integrated with F‐doped carbon dots (F‐CDs), were synthesized via a straightforward hydrothermal process and subsequent phosphatization. Attributable to precise interface engineering and electronic structure optimization, (Ni–Ru–Mo)P@F‐CDs exhibit exceptional bi‐functional catalytic activity in alkaline conditions, achieving remarkably low overpotentials of 231 and 123 mV for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively, at a current density of 100 mA cm⁻². Industrially, only 1.426 V is needed for the same efficacy. Additionally, the catalyst requires merely 1.508 and 1.564 V for overall water splitting in 1 M KOH and simulated seawater, respectively, at 100 mA cm⁻². The catalyst also shows excellent stability, with minimal performance decline over 100 h within 100–200 mA cm⁻². Density functional theory calculations indicate that the interface structure synergistically optimizes Gibbs free energy for H* and O* intermediates during HER and OER, respectively, accelerating electrochemical water‐splitting kinetics.