Comparative analysis of Titanium-doped zinc oxide (Ti-ZnO) nanophosphors synthesized via hydrothermal, Sol–Gel, and precipitation method

Nanophosphors have attracted significant attention due to their tunable optical properties and potential photocatalytic applications. In this study, titanium-doped ZnO (Ti–ZnO) nanophosphors were synthesized via hydrothermal (H–TiZnO), sol–gel (S–TiZnO), and co-precipitation (P–TiZnO) methods to evaluate the effect of synthesis route on their structural and optical properties. UV–Vis spectra showed strong absorbance of H–TiZnO in the 250–400 nm region. Tauc plot analysis revealed synthesis-dependent optical bandgaps of 2.48 eV (P–TiZnO), 3.09 eV (H–TiZnO), and 4.71 eV (S–TiZnO), confirming the strong influence of preparation method. Photoluminescence spectra showed emission peaks at ∼369 nm (H–TiZnO), ∼396 nm (S–TiZnO), and ∼402 nm (P–TiZnO), with H–TiZnO exhibiting the highest intensity, indicating improved optical quality. Dynamic light scattering results showed particle sizes of 377.47 ± 4.20 nm (H–TiZnO), 375.43 ± 1.52 nm (S–TiZnO), and 1049.67 ± 5.49 nm (P–TiZnO), while zeta potential analysis confirmed better colloidal stability for H–TiZnO. FTIR and XRD confirmed Zn–O/Ti–O bonding and the wurtzite ZnO structure with successful Ti incorporation. HRTEM and XPS further supported improved crystallinity and uniform morphology in H–TiZnO. Overall, hydrothermal synthesis produced Ti–ZnO nanophosphors with superior structural, optical, and stability properties, making them promise for optoelectronic and photocatalytic applications.