In Situ Growth of MOF-Derived NaCoPO4@Carbon for Asymmetric Supercapacitive and Water Oxidation Electrocatalytic Performance

The increasing energy crisis promotes the study on novel electrode materials with high performance for supercapacitive storage and energy conversion. Transition metal phosphates have been reported as a potential candidate due to the unique coordination and corresponding electronic structure. Herein, we adopted a facile method for preparing NaCoPO4@PC derived from a metal organic framework (MOF) as a bifunctional electrode. ZIF-67 was synthesized before a refluxing process with Na2HPO4 to form a precursor, which is transformed into the final product via calcination in different atmospheres. Specifically, the resultant NaCoPO4@PC exhibits a high specific capacitance of 1178.7 F g(-1) at a current density of 1 A g(-1) for a supercapacitor. An asymmetric supercapacitor (ASC) assembled with active carbon displays a high capacitance of 163.7 F g(-1) at 1 A g(-1). In addition, as an oxygen evolution reaction (OER) catalyst, the NaCoPO4@C electrode requires only 299 mV to drive a current density of 10 mA cm(-2) . These results suggest that the rational design of MOF-derived NaCoPO4@PC provides a variety of practical applications in electrochemical energy conversion and storage.