Carbon nanocages confined multicomponent phosphide heterostructures for boosting oxygen evolution reaction in alkaline water and seawater

Transition metal phosphides (TMPs) have appealed tremendous interests in electrocatalytic oxygen evolution reaction (OER) due to its high intrinsic activity. Nevertheless, the poor electrochemical stability in harsh condition has seriously impeded their widespread application. Herein, we develop a facile strategy for realizing the substantial improvement in OER activity and stability by simultaneously engineering multicomponent phosphide heterostructure and introducing functionalized carbon nanocages. Profiting from the synergy of triple-phased heterostructure and the highly open hollow architecture, the MOF-derived Fe2P/Ni2P/NiCoP heterostructure functionalized carbon nanocages (FeNiCoP@CNC) presents a favorable catalytic performance towards OER in 1 M KOH and alkaline seawater solutions with the low overpotentials of 237 and 245 mV at 10 mA cm−2, respectively, and no significant degradation is observed over long-term stability testing of 40 h. Detailed mechanism studies demonstrate that the triple-phased phosphide interface can facilitate the electron transfer and provide more catalytic active sites, while the functionalized carbon nanocages also boost the mass transfer and protect the FeNiCoP nanoparticles from aggregation.