3D N-doped carbon continuous network supported P-doped ZnCo2O4 nanosheets with rich oxygen vacancies for high-performance asymmetric pseudocapacitor

Abstract N-doped carbon supported MOFs derived P-doped ZnCo2O4 nanosheets (ZCP/NC) with rich oxygen vacancy are rationally designed and synthesized via a chemical heat treatment strategy. In the unique structure, N-doped carbon as a skeleton can provide an electrically conductive 3D continuous network with large surface area for the growth of active materials. P-doped ZnCo2O4 nanosheets are rich in oxygen vacancies and have a large exposure area, which can enhance the charge storage capabilities. Electrochemical measurement displayed that the novel electrodes can deliver a highest specific capacitance of 1581.5 F g−1 at 1 A g−1. An asymmetric supercapacitor (ASC) fabricated by ZCP/NC and activated carbon can reach a high energy density of 47.8 Wh kg−1 at power density of 800 W kg−1. Besides, The ASC also exhibits a cyclic retention of 90.6% for 5000 cycles. The reasons for excellent properties of ZCP/NC are discussed in detail.