Graphene Quantum Dots Coated VO2 Arrays for Highly Durable Electrodes for Li and Na Ion Batteries

• Published in: Nano letters Vol. 15; no. 1; pp. 565 - 573
• Main Authors: Chao, Dongliang, Zhu, Changrong, Xia, Xinhui, Liu, Jilei, Zhang, Xiao, Wang, Jin, Liang, Pei, Lin, Jianyi, Zhang, Hua, Shen, Ze Xiang, Fan, Hong Jin
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 14-01-2015
• Subjects: Vanadium oxides; nanoarray electrodes; lithium ion battery; graphene quantum dots; sodium ion battery
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl504038s

Nanoscale surface engineering is playing important role in enhancing the performance of battery electrode. VO2 is one of high-capacity but less-stable materials and has been used mostly in the form of powders for Li-ion battery cathode with mediocre performance. In this work, we design a new type of binder-free cathode by bottom-up growth of biface VO2 arrays directly on a graphene network for both high-performance Li-ion and Na-ion battery cathodes. More importantly, graphene quantum dots (GQDs) are coated onto the VO2 surfaces as a highly efficient surface “sensitizer” and protection to further boost the electrochemical properties. The integrated electrodes deliver a Na storage capacity of 306 mAh/g at 100 mA/g, and a capacity of more than 110 mAh/g after 1500 cycles at 18 A/g. Our result on Na-ion battery may pave the way to next generation postlithium batteries.