Iron (III) oxide, a stable semiconductor with versatile applications, was synthesized alongside Sn-doped Fe2O3 (Sn-Fe2O3) using the sol-gel technique. Characterization via X-ray diffraction, field-emission scanning electron microscopy, and UV-visible spectroscopy confirmed the presence of α- and γ-Fe2O3 phases in the synthesized powders. Incorporation of the dopant reduced the initial band gap energy of Fe2O3 (2.2 eV) by approximately 0.1 eV. To evaluate photocatalytic performance, Fe2O3 and Sn-Fe2O3 were tested for decolorization efficiency of a methyl orange solution. Results revealed the 5 wt% Sn-doped catalyst as optimal, achieving complete degradation of methyl orange within 120 min under simulated solar light. The addition of small amounts of Sn effectively reduced the Fe2O3 band gap and significantly enhanced photocatalytic performance. Investigation of pH and dye concentration impact on photocatalytic degradation revealed superior activity under acidic conditions compared to alkaline. Furthermore, maintaining a moderate concentration of methyl orange (10 ppm) ensured optimum photocatalytic activity.
There is growing interest in using corrosion inhibitors and protective treatments to limit the degradation of mild steel, leading to the development of numerous Schiff bases as cutting-edge inhibitors. In this study, the effectiveness of a Schiff base, 3-((5-mercapto-1,3,4-thiadiazol-2-yl)imino)indolin-2-one (MTIO), to prevent mild steel corrosion in HCl was investigated using weight loss measurements, potentiodynamic polarization measurements, electrochemical impedance spectroscopy techniques, and surface characterization. The experimental results showed that 0.5 mM MTIO exhibited a satisfactory inhibitor efficiency of 96.9% at 303 K. The MTIO molecules physically and chemically adsorbed onto the mild steel surface following the Langmuir model, forming a compact protective film attributed to the presence of a thiazole ring in the MTIO structure. Theoretical calculations were combined with experimental techniques to investigate the anticorrosion performance and mechanism of inhibition.