title: Toward Lower Overpotential through Improved Electron Transport Property: Hierarchically Porous CoN Nanorods Prepared by Nitridation for Lithium-Oxygen Batteries.
abstract: To lower the overpotential of a lithium-oxygen battery, electron transport at the solid-to-solid interface between the discharge product Li2O2 and the cathode catalyst is of great significance. Here we propose a strategy to enhance electron transport property of the cathode catalyst by the replace of oxygen atoms in the generally used metal oxide-based catalysts with nitrogen atoms to improve electron density at Fermi energy after nitridation. Hierarchically porous CoN nanorods were obtained by thermal treatment of Co3O4 nanorods under ammonia atmosphere at 350 °C. Compared with that of the pristine Co3O4 precursor before nitridation, the overpotential of the obtained CoN cathode was significantly decreased. Moreover, specific capacity and cycling stability of the CoN nanorods were enhanced. It is assumed that the discharged products with different morphologies for Co3O4 and CoN cathodes might be closely associated with the variation in the electronic density induced by occupancy of nitrogen atoms into interstitial sites of metal lattice after nitridation. The nitridation strategy for improved electron density proposed in this work is proved to be a simple but efficient way to improve the electrochemical performance of metal oxide based cathodes for lithium-oxygen batteries.
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Shu-Mao
authors: SM
authors: Xu
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Qian-Cheng
authors: QC
authors: Zhu
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Michelle
authors: M
authors: Harris
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Tong-Heng
authors: TH
authors: Chen
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Chao
authors: C
authors: Ma
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Xiao
authors: X
authors: Wei
authors: Hua-Sheng
authors: HS
authors: Xu
authors: Yong-Xian
authors: YX
authors: Zhou
authors: Yu-Cai
authors: YC
authors: Cao
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Kai-Xue
authors: KX
authors: Wang
authors: Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Jie-Sheng
authors: JS
authors: Chen
keywords: Low overpotential; electron density; interfacial contact; lithium−oxygen batteries; nitride