Nitrogen-doped carbon nanocones encapsulating with nickel–cobalt mixed phosphides for enhanced hydrogen evolution reaction

Abstract

In this work, nickel–cobalt mixed metal phosphides encapsulated into nitrogen-doped carbon nanocones (Ni₂P/NiCoP@NCCs) have been prepared through a facile ammonia-etching of nickel–cobalt Prussian blue analogs (Ni–Co PBAs) followed by a subsequent phosphidation treatment. During the in situ and confined phosphidation process, very small nickel–cobalt mixed metal phosphide nanocrystallites are uniformly incorporated into the simultaneously produced nitrogen-doped carbon matrix. Due to the unique structure and composition, the resultant Ni₂P/NiCoP@NCCs possess high electrocatalytic activity and excellent durability for the HER in both acidic and alkaline solutions.