• 文献标题:   Determinant influence of the electrical conductivity versus surface area on the performance of graphene oxide-doped carbon xerogel supercapacitors
  • 文献类型:   Article
  • 作  者:   RAMOSFERNANDEZ G, CANALRODRIGUEZ M, ARENILLAS A, MENENDEZ JA, RODRIGUEZPASTOR I, MARTINGULLON I
  • 作者关键词:  
  • 出版物名称:   CARBON
  • ISSN:   0008-6223 EI 1873-3891
  • 通讯作者地址:   Univ Alicante
  • 被引频次:   7
  • DOI:   10.1016/j.carbon.2017.10.025
  • 出版年:   2018

▎ 摘  要

A series of resorcinol formaldehyde based carbon xerogels were synthesized under identical conditions using different graphene oxide loads. The gelification reaction was carried out using a stable aqueous suspension of graphene oxide, yielding organic gels with graphene oxide concentrations ranging from 1.2 -2.5%. After the carbonization, xerogels with medium surface area (650 m(2)/g) and a highly improved electrical conductivity were obtained. Specific capacitance of 120 F/g of one electrode at very high scan rate of 500 mV/s were achieved, as well as power densities above 30 kW/kg, which is a significant improvement of 180% with respect to the pristine xerogels. Carbonized xerogels were further steam activated to yield activated carbon xerogels with surface areas of up to 1800 m(2)/g. The use of activated xerogels improves slightly the specific capacitance at low scan rates only, and there is a sharp decrease above 20 mV/s, resulting in a worse performance than graphene oxide doped carbonized xerogels. The electrical conductivity of the graphene oxide-doped carbon xerogels decreases upon activation, which means that the influence of the electrical conductivity on a carbon xerogel is greater than its specific surface area, which it is the first time it is observed for porous carbons. (C) 2017 Elsevier Ltd. All rights reserved.