Chemical bath deposition of SnS:Cu/ZnS for solar hydrogen production and solar cells

SnS:Cu sheet-like thin films were firstly prepared in acidic solution by chemical bath deposition (CBD). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterized the morphologies of SnS:Cu thin films. X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) and Raman spectra examined their phase purities. X-ray photoelectron spectroscopy (XPS) evaluated the valance states of elements in the films. UV-Vis-NIR diffuse reflection spectra determined their bandgaps to be 1.41–1.48 eV. The photoelectrochemical (PEC) measurements indicated that the photocurrent of SnS:Cu (20 at%) thin films had good photo-electronic responses. The fabrication of FTO/SnS:Cu (20% at)/ZnS /TiO2/Pt photocathode improved the PEC performance greatly and the photocurrent as high as 1.76 mA/cm2 had been achieved. SnS:Cu thin film solar cells were also fabricated and a power conversion efficiency of 0.3% had been achieved.