Self-Powered Photoelectrochemical Photodetectors Based on a CsPbBr3/S-g-C3N4 Heterojunction-Sensitized 3D ZnO Nanostructured Thin Film

The production of photodetectors that can provide their own power needs and can be adapted to different application conditions is very important for next-generation optoelectronic devices. Three-dimensional (3D) ZnO in nanoflower (NF) morphology was synthesized to be sensitized with all-inorganic perovskite for the application of self-powered photodetector (PD) devices. Consequently, we report high-performance and air-/solvent-stable ZnO/CsPbBr3/S-g-C3N4-based PD devices in three different forms: as a solid-state form and photoelectrochemical (PEC)-type PDs in both liquid electrolyte systems and a quasi-solid-state (QSS) form. The solid-state configuration of the PD device generated a photocurrent density of 150 μA at 367 nm, while the detectivity and responsivity values were calculated as 3.4 × 1015 Jones and 0.25 AW–1, respectively. The device was confirmed to be air-stable upon stability tests for 90 days, retaining more than 65% of its initial current density. The self-power ability of ZnO/CsPbBr3/S-g-C3N4 PEC-type PDs was proven for both liquid electrolyte systems and QSS forms. Open cell voltage and sensitivity as high as 250 mV and 3.96 × 107%, respectively, were obtained for QSS ZnO/CsPbBr3/S-g-C3N4 PEC-type PDs. This study proved that the ZnO/CsPbBr3/S-g-C3N4-based PEC PD devices with high performance in the range of 367 to 460 nm can be adapted to meet different application requirements in a wide range from liquid electrolyte systems to solid- and QSS-type electrolyte systems.