Favorable role of heterojunction in trimetallic Fe-Co-Cu phosphides on nitrogen-doped carbon materials for hydrogen evolution

Development of high-efficiency and cost-efficient electrocatalysts is vital for hydrogen generation by electrochemical water splitting. Here we report a facile two-step approach to fabricate trimetallic Fe/Co/Cu-based phosphides embedded onto nitrogen-doped carbon-graphene (FeCoCuP@NC). The FeCoCuP@NC exhibits excellent electrocatalytic hydrogen evolution reaction (HER) performance with low overpotential and durable long-term stability in both acidic and alkaline conditions. To reach a current density of 10 mA/cm(2), FeCoCuP@NC requires overpotential of 80 and 169 mV in 0.5 M H2SO4 and 1.0 M KOH, respectively. The superior HER performance of FeCoCuP@NC could be attributed to the formation of heterojunctions between different phosphides and the synergetic action between active phosphides and N-doped carbon-graphene matrix. This work affords a feasible strategy to fabricate trimetallic transition metal phosphides embedded onto carbonaceous materials using metal-organic frameworks as precursors for energy and environmental applications. (C) 2020 Elsevier Ltd. All rights reserved.