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Sulfur-doped porous reduced graphene oxide hollow nanosphere frameworks as metal-free electrocatalysts for oxygen reduction reaction and as supercapacitor electrode materials.

journal contribution
posted on 21.11.2014, 00:00 authored by X Chen, X Xu, Z Yang, Z Liu, L Zhang, Ying (Ian) ChenYing (Ian) Chen, S Huang
Chemical doping with foreign atoms is an effective approach to significantly enhance the electrochemical performance of the carbon materials. Herein, sulfur-doped three-dimensional (3D) porous reduced graphene oxide (RGO) hollow nanosphere frameworks (S-PGHS) are fabricated by directly annealing graphene oxide (GO)-encapsulated amino-modified SiO2 nanoparticles with dibenzyl disulfide (DBDS), followed by hydrofluoric acid etching. The XPS and Raman spectra confirmed that sulfur atoms were successfully introduced into the PGHS framework via covalent bonds. The as-prepared S-PGHS has been demonstrated to be an efficient metal-free electrocatalyst for oxygen reduction reaction (ORR) with the activity comparable to that of commercial Pt/C (40%) and much better methanol tolerance and durability, and to be a supercapacitor electrode material with a high specific capacitance of 343 F g(-1), good rate capability and excellent cycling stability in aqueous electrolytes. The impressive performance for ORR and supercapacitors is believed to be due to the synergistic effect caused by sulfur-doping enhancing the electrochemical activity and 3D porous hollow nanosphere framework structures facilitating ion diffusion and electronic transfer.

History

Journal

Nanoscale

Volume

6

Issue

22

Pagination

13740 - 13747

Publisher

Royal Society of Chemistry

Location

London, Eng.

eISSN

2040-3372

Language

eng

Publication classification

C Journal article; C1 Refereed article in a scholarly journal

Copyright notice

2014, The Royal Society of Chemistry