Bioconcentration and bioassembly of N/S co-doped carbon with excellent stability for supercapacitors

Herein, we demonstrate a general strategy for the preparation of nitrogen/sulfur co-doped carbon material based on hyphal bioconcentration and bioassembly, where l-cysteine and graphene oxide are added during the growth of fungal hyphae. Carbonization temperature-dependent structure and capacitance performances are discussed in detail. The results show that nitrogen/sulfur co-doped carbon obtained at carbonization temperature of 800 °C has high specific capacitance of 206 F g−1 and good rate capability of 86.1% from 1 to 20 A g−1. In addition, it shows excellent stability, including favorable temperature stability under extreme conditions (203.3 F g−1 at 60 °C and 199.9 F g−1 at 0 °C water bath), and superior capacitance stability of 93.4% retention after 10,000 cycles. The results indicate that the nitrogen/sulfur co-doped carbon material is a practically potential electrode material for supercapacitors.