▎ 摘　　要

Graphene relative materials for supercapacitors have incurred intense interest due to their high electrical and thermal conductivity, large surface area, and good chemical stability. N/P-codoped thermally reduced graphene oxide (N/P-TRGO) with high density of surface groups was synthesized by a simple way through thermal annealing of thermally exfoliated graphene oxide in the presence of (NH4)(3)PO4. The extreme low C/O atom ratio of 5.9 was reached after thermal treatment at high temperature of 800 degrees C for 2 h. N/P-TRGO exhibits high specific capacitance, high rate capability, and excellent cycle performance. The effect of codoping on the surface, structural, and electrochemical capacitive properties was investigated and elucidated in detail. These results demonstrated that N, P codoping is a convenient and efficient way for the improving the supercapacitive performance of thermally reduced graphene oxides.