Three-dimensional graphene hydrogel supported ultrafine RuO2 nanoparticles for supercapacitor electrodesElectronic supplementary information (ESI) available. See DOI: 10.1039/c5nj00062a

• Main Authors: Yang, Yuying, Liang, Yarong, Zhang, Yadi, Zhang, Ziyu, Li, Zhiming, Hu, Zhongai
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c5nj00062a

In the present work, a three-dimensional (3D) porous framework of RuO 2 /reduced graphene oxide hydrogels (RuO 2 /RGOH) was prepared by a facile one-step hydrothermal method. In this hybrid hydrogel, RuO 2 nanoparticles were homogeneously dispersed on the exfoliated RGO sheets. The as-prepared RuO 2 /RGOH electrode shows excellent supercapacitive performances with high specific capacitance (345 F g −1 for 15% RuO 2 loading), good rate capability and a long electrochemical cycling life (without decaying after 2000 cycles). Furthermore, RuO 2 in the hybrid can contribute a capacitance as high as 1365 F g −1 , which is comparable to its theoretical value. These excellent results originate from the factors that the 3D porous network structure provides a more accessible surface area and facilitates an electron and proton injecting/expelling process in the electrochemical reaction. This work provides a facile method for preparing graphene-based composite materials with remarkable capacitive performances. A 3D porous framework of RuO 2 /RGOH shows excellent supercapacitive performances, high specific capacitance, good rate capability and a long cycling life.