摘要
Obtaining stable aqueous K-ion capacitors is still challenging due to the cathode materials tended to structurally collapse after long-term cycling during large-radius K-ion insertion/extraction.In this work,three different typical MXene electrodes,i.e.,Nb_(2)C,Ti_(2)C,and Ti_(3)C_(2) were individually investigated upon their electrochemical behaviors for potassium-ion(K-ion)storage.All these MXene materials exhibited pseudocapacitive-dominated behaviors,fast kinetics,and durable K-ion storage,delivering superior performance compared with other K-ion host materials.According to the experimental results,it could be ascribed to the intrinsically large interlayer distance for K-ion transport and the superb structural stability of MXene even subjected to long-term potassiation/depotassiation process.
基金
This research was supported by GRF under Project N_CityU11305218
The work was also partially sponsored by the Science Technology and Innovation Committee of Shenzhen Municipality(No.JCYJ20170818103435068)
a Grant from City University of Hong Kong(No.9667165).
