▎ 摘　　要

Doping of heteroatoms and radicals is an important method to improve catalytic performances of graphene. However, typical heteroatom-doped methods are mostly involved in gas phase deposition or high-temperature annealing under specific gases, and need exceptional equipment and complicated technology. In this work, we explore a low temperature, thrifty, and ordinary one-step hydrothermal approach to synthesize nitrogen-sulfur dual doped reduced graphene oxide (N, S-rGO) networks at low temperature, therein thiourea was used as both nitrogen (N) and sulfur (S) sources and a reducing agent to make graphene oxide (GO) reduced synchronously with N and S in situ doping into skeleton frame of GO. The synthesized N, S-rGO has large N and S proportions (2.1 at% and 3.54 at%, respectively), and high-grade sulfur-containing types (mainly-C-S-C-) and high relative percentage pyridinic-N (44.6%) and graphitic-N (33.9%). Many open edges and defects are attached on the surface of the N, S-rGO, and it is beneficial to improve the electrocatalytic activity of oxygen reduction reaction (ORR). Electrochemical tests show that the N, S-rGO has the outstanding electrical conductivity and predominant electrocatalytic activity for ORR. Its stability and methanol tolerance are greatly enhanced compared with commercial Pt/C catalyst. The low-temperature one-step method offers the probability for the preparation of N, S-rGO in electronic devices and applications in electrode materials of fuel cells.