Anionic Biopolymer Assisted Preparation of MoO₂@C Heterostructure Nanoparticles with Oxygen Vacancies for Ambient Electrocatalytic Ammonia Synthesis

Abstract

Recently, Mo-based metal catalysts are widely applied in the electrocatalytic nitrogen reduction reaction (NRR) due to the lower binding energy between the Mo atom and N atom. The design of a Mo-based catalyst@carbon heterostructure and the introduction of anion vacancies are effective measures to improve their NRR performance. In this research, the cross-linked Vo-MoO2@C (Vo means oxygen vacancies) heterostructure nanoparticles with rich oxygen vacancies are first synthesized via pectin assisted hydrothermal reaction followed by calcination and treating with NaBH4 solution. Vo-MoO2@C exhibits good electrocatalytic NRR performance with an ammonia yield rate of 9.75 μg h–1 mg–1 at −0.5 V (RHE) and a Faraday efficiency (FE) of 3.24% at −0.3 V (RHE) under ambient conditions.