MOF-derived formation of ultrafine FeP nanoparticles confined by N/P Co-doped carbon as an efficient and stable electrocatalyst for hydrogen evolution reaction

Transition metal phosphides (TMPs) are promising candidates for the hydrogen evolution reaction (HER). FeP is a kind of highly effective and inexpensive non-noble-based HER catalyst but suffers from agglomeration and unstabilization during reaction. To solve these problems, we design a simple metal-organic-framework-derived method to synthesis N/P Co-doped carbon encapsulated ultrafine FeP nanoparticles (FeP@NPC), which exhibits outstanding activity and stability during HER. The optimized FeP@NPC presents excellent HER activity with an overpotential of 75 mV and 109 mV under the current density of 10 mA cm(-2) in 0.5 M H2SO4 and 1.0 M KOH, separately, it also exhibits outstanding stability with negligible degradation for 70 h in both acid and alkaline solution. Such impressive HER performance of FeP@NPC is mainly ascribed to the ultrafine FeP nanoparticles and the N/P co-doped carbon, which provide more active sites during reaction. Moreover, the combination of FeP nanoparticles with N/P co-doped carbon protect the FeP nanoparticles from surface oxidization, making them highly stable under HER operation. The outcome of this research opens a versatile method for preparing highly active and stable noble-metal-free electrocatalysts for hydrogen production.