Core@shell structured Au@SnO2 nanoparticles with improved N2 adsorption/activation and electrical conductivity for efficient N2 fixation
Pengtang Wang a,1 , Yujin Ji b,1 , Qi Shao a , Youyong Li b , Xiaoqing Huang a, *（黄小青）
a College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
b Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
1 These authors contributed equally to this work.
Science Bulletin 65 (2020) 350--358
The design of electrocatalysts with enhanced adsorption and activation of nitrogen (N2) is critical for boosting the electrochemical N2 reduction (ENR). Herein, we developed an efficient strategy to facilitate N2 adsorption and activation for N2 electroreduction into ammonia (NH3) by vacancy engineering of core@shell structured Au@SnO2 nanoparticles (NPs). We found that the ultrathin amorphous SnO2 shell with enriched oxygen vacancies was conducive to adsorb N2 as well as promoted the N2 activation, meanwhile the metallic Au core ensured the good electrical conductivity for accelerating electrons transport during the electrochemical N2 reduction reaction, synergistically boosting the N2 electroreduction catalysis. As confirmed by the 15N-labeling and controlled experiments, the core@shell Au@amorphous SnO2 NPs with abundant oxygen vacancies show the best performance for N2 electroreduction with the NH3 yield rate of 21.9 μg h−1 mg−1cat and faradaic efficiency of 15.2% at −0.2 VRHE, which surpass the Au@crystalline SnO2 NPs, individual Au NPs and all reported Au-based catalysts for ENR.