N, P co-doped microporous carbon derived from the central part of corn cob for high-performance symmetrical supercapacitors

A kind of N, P co -doped carbon material containing only micropores was prepared from the central part of corn cob. The effect of activation temperature on product structure and capacitive properties was studied in detail. The characterization results show that the carbon material (NPCC-650) prepared at 650 degrees C has high content of heteroatoms, large specific surface area and abundant micropores. Due to the structural advantages of NPCC650, electrochemical tests show that the specific capacitance and rate properties of NPCC-650 are significantly better than the samples prepared at 550 degrees C and 750 degrees C. In addition, the symmetric supercapacitor assembled based on NPCC-650 has a specific capacitance of 45.8 F g -1 at a current density of 0.5 A g -1 , corresponding to the energy density of 12.5 Wh kg -1 . This research not only provides a method for the high valueadded utilization of agricultural waste, but also provides an idea for the preparation of cheap and highperformance micropore carbon -based electrodes.