Physical Vapor Deposited [Co:Cd-(dtc)2]/SnO2 Dual Semiconductor Systems: Synthesis, Characterization and Photo-Electrochemistry

Abstract

Current work reports the fabrication of cadmium, cobalt and cobalt doped cadmium semiconductor chalcogenide [Cd-(dtc)2 [dtc = dithiocarbmate], Co-(dtc)2, and Co:Cd-(dtc)2] complexes using iso-propylammonium dithiocarbamate precursor grown into thin films via physical vapor deposition (PVD) for the first time. Cubic crystals having 18 nm of average size were revealed via X-ray diffraction. Varied molecular arrangements and bonding types were disclosed by Fourier transform infrared spectroscopy. Bandgap tailoring was done by doping leading to a broadening in bandgap i.e., 3.72, and 3.5 eV direct and indirect bandgaps, respectively through ultra-violet visible spectrophotometry. PVD grown thin films indicated formation of clusters and irregular structures between the gaps and voids of micro-grains shown by field emission scanning electron microscopy. Rutherford back scattering spectroscopy expressed the remarkable thickness i.e., 615 nm with stronger signals for Cd, Co and S elements. Furthermore, the electrochemical analysis of the pristine and doped chalcogenide thin films done via cyclic, linear sweep voltammetry and chronoamperometry elucidated the excellent photo-response and functional stability and confirmed the potential of these films as future candidates for multitudinous photovoltaic and optoelectronic devices especially the utilization of [Co:Cd-(dtc)2]/SnO2 thin films in solar cell devices is expected to yield higher through put potentials and photo-currents if sandwiched between the active absorber layer and photo-electrodes.