Improving photocatalytic performance: Creation and assessment of nanostructured SnO2 thin films, pure and with nickel doping, using spray pyrolysis

Abstract

This study investigates conductive, transparent films of undoped and Ni-doped SnO2 deposited through water solvent spray pyrolysis, aiming to combat environmental water pollution. Examining these films using X-ray diffraction (XRD), Fourier transform infrared absorption microscopy (FTIR), UV–Vis spectrophotometer, and Hall effect, the research focuses on photocatalytic degradation kinetics using rhodamine B (RhB) as a model pollutant from the textile industry.XRD results confirm tetragonal structures of SnO2 and Ni: SnO2 films with crystallite sizes ranging from 21.83 to 19.52 nm. The sprayed films exhibit resistivity variations (7.1 × 10−3 to 4.5 × 10−3) Ω.cm and figure of merit variations [(1.49 × 10−4 to 25.03 × 10−4); (2.69 × 10−4 to 9.1 × 10−4)] (Ω/sq)−1. Optical properties include ∼73% light transmission, ∼20% reflection, and ∼7% absorptance, with porosity (8.65–11.44)%, refractive index (2.88–1.57), extinction coefficient (0.0043–0.0013), dielectric constants (8.31–2.48 and 0.025–0.0041), optical density [(3.9 × 10+10–7.86 × 10+09) S−1], skin depth [(2.06 × 10−3–6.7 × 10−3) cm−1], and optical band gap with Urbach energy [(3.8–3.6) eV and (0.67–0.43) eV] obtained at 550 nm.The photocatalytic process, crucial for water pollution treatment, exhibits pH sensitivity (12.3–1.7) over varied times (0–90 min) and is influenced by the SnO2 thin film elaboration method. Notably, 0.5 M-concentration SnO2 films show the most efficient photocatalytic degradation rates. This research highlights the potential of SnO2 in environmentally friendly water pollution treatment, emphasizing its practical application in addressing crucial environmental challenges.