Cerium Zirconium Solid Solution with High Faradaic Efficiency for Electrochemical Nitrogen Reduction Reaction under Ambient Condition

Abstract

Industrial synthesis of ammonia (NH 3 ) involves high energy consumption resulting in intense pollution. Alternatively, electrochemical nitrogen reduction reaction (NRR) to NH 3 can be carried out under mild conditions, which is a new green NH 3 synthesis method. Herein, cerium zirconium solid solutions (Zr x Ce 1-x O 2 ) with different proportions were synthesized by NH 3 precipitation method and employed as electrocatalysts for NRR. The performance of the different catalysts in 0.1 mol L À 1 Na 2 SO 4 was evaluated with H 2 O and N 2 as reactants. The results show that Zr 0.9 Ce 0.1 O 2 has the highest Faraday efficiency (FE) of 62.68 % at À 1.3 V (vs. Ag/AgCl) and the highest yield rate of NH 3 À 9.34 × 10 À 11 mol cm À 2 s À 1 at À 1.35 V (vs. Ag/AgCl). The impressive FE is due to more oxygen vacancies in Zr 0.9 Ce 0.1 O 2 introduced by Ce 3 + , which is more prone to the adsorption of N 2 on the catalyst surface and facilitates the electrochemical reaction.