Zn-doped TiO2 nanoparticles: enhanced catalytic and nonlinear optical properties

Abstract

Abstract The present study explores the nonlinear optical (NLO) properties and catalytic activities of Zn-doped titania nanoparticles (NPs) synthesized by the sol–gel method. Structural and morphological characterizations confirm the successful doping of Zn into the crystal lattice of titania, and the formation of irregular shape and size NPs is observed. Energy bandgap and Urbach energy calculated by the optical characterization of the fabricated Zn-doped TiO 2 NPs, which are determined to be 3.37 eV and 1.07 eV, respectively, which are higher than the corresponding values for pure TiO 2 . The NLO parameters are studied using the Z-scan measurement technique, confirming that Zn-doped TiO 2 exhibits appreciable nonlinear absorption owing to its reverse saturation absorption. Further, open- and closed-aperture Z-scans confirm the two-photon absorption and self-defocusing effect. Rhodamine B (96% in 4 min), methylene blue (97.9% in 10 min), and 4-nitrophenol (89.1% in 20 min) are used to investigate the sample’s catalytic dye degradation and reduction efficiency. The prepared NPs are suitable for efficient wastewater treatment and NLO applications.