Identifying the role of interface chemical bonds in activating charge transfer for enhanced photocatalytic nitrogen fixation of Ni2P-black phosphorus photocatalysts

Abstract

Efficient charge transfer plays a key factor in regulating the N2 reduction activity of photocatalyst, it is still challenging to steer the charge transfer in a precise approach. Herein, smartly-designed Ni2P-black phosphorus (Ni2P-BP) photocatalysts with abundant interface NiP bonds were synthesized by selectively growing of Ni2P at the edge of BP nanosheets. The interface NiP bonds between Ni2P and BP acted as atomic level electron transfer channels reduces the potential energy barrier for interface charge transfer, resulting in enhanced NH3 production activity. The Ni2P-BP photocatalyst achieves 100 % selectivity for photocatalytic N2 reduction to NH3 with the highest NH3 generation rate of 6.14 μmol·h−1·g−1, which is 1.56 times higher than the NiP bond-free Ni2P nanoparticles loaded BP (Ni2P+BP) photocatalyst. More importantly, the Ni2P grown at the edge of BP passivates the reactivity of edge P atoms, significantly improving the stability of BP for photocatalytic nitrogen fixation.