Dual visible light photocatalytic fuel cell for efficient degradation of model organic pollutants using CdS/TiO2 photoanode and TiO2/CuS photocathode

A single-chamber photocatalytic fuel cell (PFC) employing a TiO2/CuS photocathode and CdS/TiO2 photoanode is designed for the simultaneous degradation of a model organic pollutant and electricity generation. The Fermi levels of the TiO2/CuS photocathode (p-type semiconductor) and CdS/TiO2 photoanode (n-type semiconductor)-residing in the CuS valence band and anodic TiO2 conduction band, respectively-create a favorable internal bias between the photoelectrodes. The presence of anodic CdS and cathodic TiO2 enhances electron-hole separation, thereby improving cell performance. Characterized by XRD and HRTEM, the structural analysis confirms the hexagonal crystal structure for both CdS and CuS, while TiO2 exhibits a tetragonal crystal system. These synthesized photoelectrodes were evaluated in a PFC operating with 10% volumetric ethanol fuel, 0.2 M KOH electrolyte, and 6500 Lux illumination from two compact fluorescent lamps. The achieved maximum current density (ISC), potential (VOC), and power density (PMAX) were 136.6 mu A cm(-2), 0.779 V, and 43.2 mu W cm(-2), respectively, indicating promising cell performance. Furthermore, the study suggests that augmenting light intensity, electrolyte and fuel concentration, optimizing solution pH, and utilizing simple organic fuels significantly enhance electricity production and overall cell efficiency.