High-performance Li-ion batteries based on graphene quantum dot wrapped carbon nanotube hybrid anodes  

作　　者：Xuewei Zhao Yizeng Wu Yunsong Wang Huaisheng Wu Yawei Yang Zhipeng Wang Linxiu Dai Yuanyuan Shang Anyuan Cao 

机构地区：[1]Department of Materials Science and Engineering,College of Engineering,Peking University,Beijing 100871,China [2]School of Physics and Microelectronics,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Nano Research》2020年第4期1044-1052,共9页纳米研究（英文版）

基　　金：A.Y.C.appreciated the financial support from the National Natural Science Foundation o f C hina(No.51672005).S.Y.Y.appreciated the financial support from the National Natural Science Foundation of China(No.51872267).Z.X.W.thanks Qihang Gong for his support and encouragement all the time.

摘　　要：Since Akira Yoshino first proposed the usage of the carbonaceous materials as an anode of lithium ion batteries(LIBs)in 1985,carbonaceous materials such as graphite and graphene have been widely considered as LIB anodes.Here,we explored the application of novel carbonaceous UB anodes incorporating graphene quantum dots(GQDs).We fabricated a freestanding all-carbon electrode based on a porous carbon nanotube(CNT)sponge via a facile in-situ hydrothermal deposition technique,creating coaxial structure of GQD-coated CNTs(GQD@CNTs)through electrostatic interaction and n-n stacking with tunable loading and functionalization.This hybrid structure combined conductive CNTs with highly active GQDs,in which GQDs with predesigned functional groups provided massive storage sites for Li ions and the 3D CNT frameworks avoided the agglomeration of GQDs,together contributing to a high specific capacity(700 mAh·g^-1 at 100 mA·g^-1 after 100 cycles)and rate performance.Even at a high current density of 1,000 mA·g^-1,the reversible specific capacity remained at 483 mAh g-1 after 350 cycles.In particular,the mechanism study demonstrated the important role of oxygen functional groups of GQDs in promoting the performance of the LIB anodes by controlled grafting of GQDs onto various porous-carbon and metal-foam based structures.

关 键 词：graphene quantum dots carbon nanotubes lithium ion batteries anodes oxygen functional groups 

分 类 号：TM912[电气工程—电力电子与电力传动] TB383[一般工业技术—材料科学与工程]