摘要
The V_2C compound,belonging to the group of two-dimensional transition metal carbonitrides,or MXenes,has demonstrated a promising electrochemical performance in capacitor applications in acidic electrolytes;however,there is evidence to suggest that V_2C is unstable in an acidic environment.On the other hand,the performance of V_2C in neutral aqueous electrolytes is still moderate,and has not yet been systematically studied.The charge storage mechanism in a V_2C electrode,employed in neutral aqueous electrolytes,is investigated via cyclic voltammetry testing and in situ x-ray diffraction(XRD).Good specific capacitances are achieved,specifically208 F/g in 0.5 M Li_2SO_4,225 F/g in 1 M MgSO_4,120 F/g in 1 M Na_2 SO_4,and 104 F/g in 0.5 M K_2SO_4.Using in situ XRD,we observe that,during the charge and discharge process,the c-lattice parameter shrinks or expands by up to 0.25 A in MgSO_4,and 0.29 A in Li_2SO_4 which demonstrates the intercalation/de-intercalation of cations into the d-V_2C layer.
作者
陈超凡
庞迪
王晓彤
陈岗
杜菲
高宇
Chaofan Chen;Di Pang;Xiaotong Wang;Gang Chen;Fei Du;Yu Gao(Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education),College of Physics,Jilin University,Changchun 130012,China;State Key Laboratory of Superhard Materials,College of Physics,Jilin University,Changchun 130012,China)
基金
Supported by the Science&Technology Department of Jilin Province (Grant Nos.20180101199JC and 20180101204JC)
Jilin Province/Jilin University Co-construction Project-Funds for New Materials (SXGJSF2017-3)。