abstract
Semiconductor films play a crucial role when it comes to modern solar-based technologies to generate
electricity, produce solar fuels, or convert the environmental pollutants to other harmless materials. In
this paper, using an interesting simple as well as versatile electrochemical route, a nanocomposite Cu/
Zn/Sn oxide semiconductor film was fabricated on a fluorine doped tin oxide glass and investigated as a
photocathode of quantum dot solar cells in a sulfide/polysulfide electrolyte solution. X-ray diffraction
analyses revealed a composite nature for this electrodeposited film. A broadband light absorption was
witnessed and the band gap (1.63 eV) was determined through Tauc's procedure. Scanning electron
micrographs exhibited a non-smooth morphology for this composite film, which provides a greater area
for heterogeneous reactions occurring upon the electrode surface. Mott–Schottky and potentiodynamic
polarization plots indicated that the fabricated electrode acts as a complex p-type photocathode. The
electrochemical impedance studies proved that under light irradiation, by photo-generation of charge
carriers (electron-hole), the interfacial charge transfer resistance decreases and the cathodic current
becomes consequently enhanced. After coating (photodeposition) with silver, a complicated photoelectrochemical
response was finally observed and the findings were explained in detail