Electrodeposition of SnSe thin film using an organophosphorus [(Me2)3N3PSe] precursor for photovoltaic application

One prevalent class of thin films concerns SnSe (tin selenide), which is the primary focus of this research, with the aim of discovering cost-effective coatings for photovoltaic applications. The electrodeposition method was employed to successfully synthesize tin selenide thin films on glass substrates (ITO and FTO) utilizing the novel organophosphorus precursor [(Me2)3N3PSe]. Notably, this precursor has not been utilized in prior literature. Initial cyclic voltammetry (CV) analyses were performed to thoroughly investigate the electrochemical behavior of the tin and selenium redox systems within the electrolyte. The CV outcomes yielded crucial insights, guiding the establishment of a defined potential range (− 1.1 to − 1.2 V vs. SCE) for effective SnSe film electrodeposition. Films deposited within this potential range exhibited characteristic needle-shaped polycrystalline SnSe structures. Comprehensive analyses of the thin films’ structural, microstructural, and morphological characteristics were conducted, employing X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS). The crystallites’ size was determined using the Debye–Scherrer formula. Moreover, a systematic exploration of the impact of deposition potential and substrate type on various film properties was undertaken. The results from XRD and Raman spectroscopy confirmed the formation of an orthorhombic single-phase SnSe under different deposition potentials. SEM/EDS analysis revealed uniform element distribution for deposition potentials of − 1.1 V and − 1 V on ITO and FTO substrates, respectively. The investigation further extended to the optical properties of films on glass substrates (ITO and FTO). Optical data showed a direct optical band gap (Eg) ranging from 1.25 to 2.24 eV for ITO and 1.46 to 2.87 eV for FTO across a wide spectra range. These optical traits, significantly influenced by deposition potential and substrate type, hold promise. Particularly, SnSe thin films deposited on ITO substrates at − 1.1 V displayed distinct advantages for potential photovoltaic applications compared to samples on FTO substrates. Graphical Abstract: [Figure not available: see fulltext.]