ZnO/g-C3N4 heterostructures: Synthesis, characterization and application as photoanode in dye sensitized solar cells

A simple low-temperature hydrothermal route was adopted to prepare the binary ZnO/g-C3N4 heterostructures, which were thoroughly characterized by various spectroscopic and microscopic probes. The clearly visible interfaces between the ZnO NRs and g-C3N4 in the HRTEM micrograph verify the formation of ZnO/g-C3N4 heterojunction structures, which, combined with N3 dye, deliver increased optical absorption extending from UV to the visible range. The binary ZnO/g-C3N4 heterostructures are used as the photoanode in the DSSC application. Improvement in the DSSC performance arises because of the growth of the g-C3N4 layer on the ZnO nanorods surface, which efficiently delays the reverse recombination of electrons from ZnO to the electrolyte. The g-C3N4 layer also increases the electron concentration in the photoelectrode and, thereby, directly contributes to the improved performance of the DSSC device. The optimal DSSC based on the ZnO/g-v photoanode delivers its characteristic J(SC) similar to 14.18 mA/cm(2), V-OC similar to 544 mV, FF similar to 0.586 and. similar to 4.52%, which is about 2.3 times greater than the DSSC efficiency based on pure ZnO nanorod photoelectrode and retains the spirit of generating the green energy following the photovoltaic endeavor.

Automated summary

A simple low-temperature hydrothermal route was used to prepare binary ZnO/g-C3N4 heterostructures, which showed improved performance in DSSC application. The growth of g-C3N4 layer on ZnO nanorods surface delayed electron recombination and increased electron concentration in the photoelectrode.