Green synthesis preparation and evaluation of CuO doped SnO₂

Tetrakis (diethylamino)tin (IV) (TDMASn) ((C₂H₅)₂N)₄Sn is an organometallic tin precursor with excellent purity that is used in the atomic layer deposition (ALD) technique. Due to the high expense of ALD equipment, the use of this precursor for the manufacture of nanocrystalline tin oxide (SnO₂) thin films has been limited. In this study, copper oxide (CuO) doped tin oxide (SnO₂) was prepared using TDMASn as SnO₂ precursor, copper (II) sulphate pentahydrate (CuSO₄·5H₂O) as Cu precursor and a green catalyst (Allium cepa) as a reducing agent via spin coating technique and deposited on a glass substrate. The deposited thin film was then annealed and characterized using, X-ray diffraction (XRD), scanning electron microscope (SEM), elemental composition (EDX), UV–Visible (UV–Vis) spectroscopy, Fourier transform infrared (FTIR), and electrical analysis. The correlation between the different analyses with regards to the calcining temperature of the fabricated thin film was discussed. A redshift was observed in the optical energy band gap of the film. Also, the film's electrical properties demonstrated ideal semiconducting behaviours.