Preparation of photoreactive cathodes from copper-based metal-organic frameworks and their application in aqueous zinc-ion hybrid supercapacitors

To further enhance the energy density of aqueous zinc-ion hybrid supercapacitors, this paper verifies the feasibility of using copper catecholate (Cu-CAT) a copper-based metal-organic framework (MOF) characterized by strong broadband light absorption, good electrical conductivity, and a large specific surface area as a photoactive material. When used as the photoactive cathode in a Zn//Cu-CAT@CC aqueous zinc-ion hybrid supercapacitor, it can convert and store solar energy in the electrodes. Under sunlight, at a current density of 1 mA cm2, the device's areal capacity reaches 0.162 mAh cm2, an 89.1% increase over the storage capacity without light. This not only opens up new areas for the application of Cu-CAT materials but also offers more possibilities for the development of aqueous zinc-ion hybrid supercapacitors.