Ni2P hollow microspheres for electrocatalytic oxygen evolution and reduction reactions†
Ni2P hollow microspheres were synthesized and examined as an electrocatalyst for both O2 evolution and reduction reactions. This hollow microsphere structure, assembled from ultrathin nanosheets, has a high surface-to-volume ratio and is beneficial for fast charge transfer and mass diffusion. This Ni2P material is efficient for water oxidation, achieving a 10 mA cm−2 current at a 280 mV overpotential. It is also effective in catalyzing the reduction of O2 with an onset potential of 0.92 V, representing a rare example of Ni phosphides as O2 reduction catalysts.