Water system hybrid supercapacitor electrode material and preparation method and application thereof

The invention discloses a preparation method of a water system mixed type supercapacitor electrode material based on Ni-doped Co3O4 (at) C. The preparation method comprises the following steps: dissolving NH4Cl in ammonia water, then adding porphyrized CoCl2 and porphyrized NiCl2 batch by batch in batches, and continuously stirring by using a glass rod in the dissolving process to obtain a yellow red turbid solution; under a stirring state, dropwise adding an H2O2 solution into the yellow red turbid solution to obtain a purple red solution; dropwise adding concentrated hydrochloric acid into the purplish red solution, and separating out a purplish red precipitate after dropwise adding; adding activated carbon, heating for a period of time in a steam bath, then cooling to room temperature, carrying out suction filtration, washing and airing to obtain a dark purple solid [Co0. 97Ni0. 03 (NH3) 5Cl] (at) C; and the mixture is put into a muffle furnace to be calcined, and black powdery solid Ni-doped Co3O4 (at) C