Fine rhodium phosphides nanoparticles embedded in N, P dual-doped carbon film: New efficient electrocatalysts for ambient nitrogen fixation

Abstract

Constructing high-efficient and cost-saving catalysts for electrochemical nitrogen reduction reaction (NRR) under ambient conditions is of great significance, but quite challenging. Herein, a series of foam-like composites comprised of small RhPx nanoparticles (NPs) and N, P co-doped carbon (NPC) framework are first reported as novel high-efficiency NRR electrocatalysts. Interestingly, the electronic structure and catalytic behavior of RhPx are modified by altering the contents of P in composites. Density function theory (DFT) calculations prove that the introduction of P into the rhodium lattice can dramatically reduce the catalytic reaction barrier and facilitate the intermediate process of catalytic reaction. Compared with most of the reported materials, this new catalyst possesses high ammonia (NH3) yield rate of 37.6 μg h−1 mgcat.-1 and Faraday efficiency (FE) of 7.64 %, as well as good selectivity and superior stability in acid conditions. This work provides a theoretical basis and practical scheme for the wide application of other robust transition metal phosphides electrocatalysts in NRR.