EN13.08.09 : Oxygen Vacancies Enhance the Li+ Intercalation Pseudocapacitive Properties of T-Nb2O5

5:00 PM–7:00 PM Apr 5, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E

Songmin Zhang1 Jitong Wang1 Licheng Ling1 Wenming Qiao1 Donghui Long1

1, State Key Laboratory of Chemical Engineering, Shanghai, , China

While orthorhombic (T-) Nb2O5 is one of the most promising energy storage material with rapid Li+ intercalation pseudocapacitive response, a key challenge remains in the realization of high-rate charge-transfer reaction when fabricated into thick electrodes. Herein, a facile gas reduction method is demonstrated for Nb2O5 nanoparticles treated with H2 to create intrinsic defects. The specific capacitance for hydrogenated (H-) Nb2O5 at 0.5 A g-1 reaches 649 C g-1, exceeding that of T-Nb2O5 with only 569 C g-1, which suggests numbers of active sites resulting from the formation of oxygen vacancies. In addition, the successful introduction of oxygen vacancies leads to enhanced electrical conductivity and increased donor density that accelerates charge storage kinetics and enables excellent long-term cycling stability. This work are of great importance to provide a new insight into improving the electrochemical properties of various transition metal oxides by incorporating oxygen vacancies.