MXene has given great promises to superca-pacitor electrode material due to its high conductivity and redox properties.However,the self-agglomeration of the MXene lamella will reduce its contact area with the elec-tro...MXene has given great promises to superca-pacitor electrode material due to its high conductivity and redox properties.However,the self-agglomeration of the MXene lamella will reduce its contact area with the elec-trolyte and generate a tortuous transportation pathway of the electrolyte ions,thereby reducing its capacitive per-formance and rate capability.In this work,we engineered the electrolyte ion channels by adjusting the MXene lamella size and inserting holey graphene(HG)nanosheets into the interlayer of the MXene flakes.The developed MXene/HG electrode can not only avoid the self-restack-ing of MXene but also provide unimpeded ion transport channels.As a result,the supercapacitive and rate perfor-mances of the small MXene lamella-based MXene/HG(S-MXene/HG)supercapacitor are prominently ameliorated.By adjusting the content of HG,the S-MXene/HG0.05 electrode exhibits excellent gravimetric capacitance of 446 F·g^(-1)and a rate capability of 77.5%.The S-MXene/HG0.05-based symmetric supercapacitor provides an impressive energy density of 14.84 Wh·kg^(-1)with excellent cyclic stability of 96%capacitance retention after 10,000 cycles.This demonstration of the engineering of the ion channels shows great potential in two-dimensional mate-rial-based supercapacitor electrodes.展开更多
基金financially supported by the National Key R&D Program of China (No.2017YFA0304203)the National Natural Science Foundation of China (Nos.21805174 and 51902190)+5 种基金the Key Research and Development Program of Shanxi Province for International Cooperation (No.201803D421082)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (Nos.2019L0013 and 2019L0018)Shanxi Scholarship Council of China (No.2021-004)the Program of Introducing Talents of Discipline to Universities (No.D18001)the Changjiang Scholars and Innovative Research Team at the University of Ministry of Education of China (No.IRT_17R70)the Fund for Shanxi “1331 Project”
文摘MXene has given great promises to superca-pacitor electrode material due to its high conductivity and redox properties.However,the self-agglomeration of the MXene lamella will reduce its contact area with the elec-trolyte and generate a tortuous transportation pathway of the electrolyte ions,thereby reducing its capacitive per-formance and rate capability.In this work,we engineered the electrolyte ion channels by adjusting the MXene lamella size and inserting holey graphene(HG)nanosheets into the interlayer of the MXene flakes.The developed MXene/HG electrode can not only avoid the self-restack-ing of MXene but also provide unimpeded ion transport channels.As a result,the supercapacitive and rate perfor-mances of the small MXene lamella-based MXene/HG(S-MXene/HG)supercapacitor are prominently ameliorated.By adjusting the content of HG,the S-MXene/HG0.05 electrode exhibits excellent gravimetric capacitance of 446 F·g^(-1)and a rate capability of 77.5%.The S-MXene/HG0.05-based symmetric supercapacitor provides an impressive energy density of 14.84 Wh·kg^(-1)with excellent cyclic stability of 96%capacitance retention after 10,000 cycles.This demonstration of the engineering of the ion channels shows great potential in two-dimensional mate-rial-based supercapacitor electrodes.
