Premium
High Performance Flexible Supercapacitor Electrodes Composed of Ultralarge Graphene Sheets and Vanadium Dioxide
Author(s) -
Lee Myungsup,
Wee BoonHong,
Hong JongDal
Publication year - 2015
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.201401890
Subject(s) - graphene , materials science , supercapacitor , electrode , oxide , electrochemistry , capacitance , nanotechnology , sheet resistance , chemical engineering , layer (electronics) , chemistry , engineering , metallurgy
Little is known regarding the effect of the graphene lateral size on the electrochemical performance of hybrid graphene electrode. This work examines the electrochemical performance of a flexible hybrid supercapacitor electrode composed of ultralarge graphene oxide (UGO; mean lateral size of 47 ± 22 μm) and vanadium dioxide (VO 2 ) nanobelts, referring to a reference electrode composed of small scale graphene oxide (SGO; mean lateral size of 0.8 ± 0.5 μm) and VO 2 .Thermal treatment converts UGO/VO 2 and SGO/VO 2 to URGO/VO 2 (denoted VURGO) and SRGO/VO 2 (denoted VSRGO) electrodes, respectively. The sheet resistance of the VURGO film (0.57 ± 0.03 kΩ sq. –1 ) was two orders of magnitude lower than that of the VSRGO (55.74 ± 9.35 kΩ sq. –1 ). The VURGO hybrid electrode showed a specific capacitance of 769 F g −1 , which was significantly better than the corresponding values for the VSRGO electrode (385 F/g). These results support the notion that the use of ultralarge graphene sheets (≈22 500 μm 2 ) lowers the intersheet resistance due to the presence of fewer intersheet tunneling barriers. This article highlights the potential utility of URGO (as a conductive support) in hybrid electrode containing VO 2 nanobelts for high performance flexible hybrid supercapacitor.