Prussian blue analog‐derived bimetallic phosphide nanoparticles anchored in nitrogen‐doped porous electrospun carbon nanofibers for efficient oxygen evolution reaction

Abstract

Prussian blue analogs (PBAs) and their derivatives have been extensively investigated as potential oxygen evolution reaction (OER) electrocatalysts due to their high specific surface areas, adjustable composition, and controllable morphology, yet they suffer from easy aggregation and poor electrical conductivity. Herein, we successfully synthesized PBA‐derived NiFe bimetallic phosphide nanoparticles encapsulated in porous nitrogen‐doped electrospun carbon nanofibers by sequential electrospinning, carbonization, and phosphorization. By exploring the effects of different phosphating temperatures on electrocatalytic performance, the obtained electrocatalyst possesses a low overpotential of 262 mV at 10 mA cm−2 for OER in 1.0 M KOH. The electrospun carbon nanofibers can not only address the problem of poor electrical conductivity of PBA derivatives but also provide confinement effect, which could reduce PBA aggregation and collapse. Furthermore, the coupling effect of porous nitrogen‐doped electrospun carbon nanofibers and PBA‐derived bimetallic phosphide nanoparticles facilitates sufficient exposure of active species, expedites electron transfer, accelerates reaction kinetics, and improves durability.