Influence of deposition temperature on the structural, morphological, optical and photoelectrochemical properties of CBD deposited Cu₂SnS₃ thin films

The Cu₂SnS₃ (CTS) thin films are deposited onto conducting stainless steel (SS) substrates using a low-cost chemical bath deposition method. The influence of deposition temperature on the structural, morphological, optical and photoelectrochemical (PEC) properties of CTS thin films is investigated. The XRD patterns of CTS films demonstrate nanocrystalline nature and triclinic crystal structure. The compositional data verify the presence of copper, tin, and sulfur in their relevant oxidation states. Surface morphology reveals that the deposition temperature influences the surface morphology of CTS thin films. The optical absorption study reveals a direct energy gap between 1.73 and 1.57 eV. With increasing deposition temperature from 323 to 353 K, the photoconversion efficiency is improved from 0.10 to 0.40%. In conjunction with PEC performance, the electrochemical impedance spectra of all the samples are analyzed.