Analytical evaluation of nickel strontium lanthanum titanate nanoparticles synthesized via Pechini sol–gel method for the degradation of acid red 88

A facile Pechini sol–gel method was employed to synthesize nickel strontium lanthanum titanate nanoparticles (NiSrLaTiO6, NSLTO), followed by comprehensive physicochemical and analytical characterization. The structural and morphological properties were investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR), confirming the formation of nanoscale spherical particles with high crystallinity. Optical properties were evaluated using diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) analysis, revealing an optical band gap of 2.88 eV and enhanced visible-light absorption behavior. The photocatalytic performance of NSLTO nanoparticles was monitored analytically by the degradation of Acid Red 88 (AR88), a model organic pollutant, under visible-light irradiation. Quantitative analysis using UV–Vis spectrophotometry demonstrated a degradation efficiency of 91.4% after 180 min, significantly higher than that of pure TiO₂ nanoparticles (23.5%) under identical conditions. The effects of operational parameters, including catalyst dosage, solution pH, and oxidizing agents, were systematically optimized and evaluated to establish analytical performance and degradation efficiency. Kinetic analysis indicated that the degradation process follows pseudo-first-order reaction behavior, confirming the high catalytic activity of NSLTO nanoparticles. Additionally, the catalyst's reusability and stability were assessed over seven successive cycles, with negligible loss of activity. These results highlight the potential of NSLTO nanoparticles as an efficient visible-light-driven photocatalyst for environmental remediation and provide a reliable analytical approach for monitoring dye degradation in aqueous systems.