W/Mo-polyoxometalate-derived electrocatalyst for high-efficiency nitrogen fixation

Abstract

Ammonia is the feedstock chemical for most fertilizers and the alternative of renewable energy carriers. Environmentally benign electrochemical nitrogen reduction reaction (NRR) under mild conditions has been recognized as one of the most attractive strategies for N2 fixation. Herein, inspired by Mo-based nitrogenase, W/Mo-doping electrocatalysts were developed with mixed-metal polyoxometalate H3PW6Mo6O40 as the precursor for high performance electrocatalytic NRR. Trace amount of Pt was transplanted on the surface of W/[email protected] via in situ electroplating treatment to further improve the NRR performance. The resulting Pt-W/[email protected] achieves excellent performance for NRR with a high NH3 yield of 79.2 µg h−1 mgcat−1 due to the multicomponent synergistic effect in the composite catalyst. The Pt-W/[email protected] represents the first example of highly efficient NRR electraocatalyst derived from mixed-metal polyoxometalate, which exhibits outstanding stability confirmed by the constant catalytic performance over 24 h chronoamperometric test. This finding opens a new avenue to construct highly efficient NRR electrocatalyst by employing mixed metal polyoxometalate as the precursor under ambient conditions.