Photoelectrochemical In Situ Energy Storage and the Anticorrosion Dual Function System Based on Loose Carbon Nitride Thick Film Electrodes

The photoelectrochemical application system with in situ energy storage and anticorrosion dual function is constructed, in which a loose morphology carbon nitride thick film electrode prepared by the one-step gas expansion strategy is used as a photoanode, and photoelectrochemical anticorrosion performance is used as an evaluation. The long-range electron path resulted from the structure design can cause certain delay of the recombination of photocarriers, which facilitates the realization of simultaneous energy storage and anticorrosion for this system. The loose morphology promotes the ion transfer kinetics, shortens the energy storage time (20 times) greatly, and broadens the capacity (160 mV). The energy storage efficiency of this system is up to 50%, and the discharge time (discharge to −0.7 V) is 3000 times that of the system based on the compact carbon nitride film electrode. Moreover, the photoelectrochemical anticorrosion efficiency is increased by 82 times and can provide as long as 6 h cathodic protection for carbon steel.