Vol. 13, Issue 6 (2025)

In the present work, ?-cyclodextrin (?-CD) assisted ZnO-SiO? nanocomposites were synthesized via a co-precipitation route using zinc sulphate heptahydrate and SiO? powder, followed by thermal treatment/calcination to obtain stable nanocomposite materials. Different ZnO loadings (ZS1, ZS3, ZS5 and ZS7) were prepared by varying the ZnO content and adding ?-CD as a stabilizing agent. The prepared materials were characterized using X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV-DRS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray analysis (SEM-EDX). XRD patterns confirm amorphous silica features with the progressive appearance and enhancement of crystalline ZnO-related peaks as the ZnO loading increases, indicating the successful incorporation of ZnO into the SiO? matrix and the formation of a hybrid structure at higher loadings. UV-DRS results demonstrate tunable optical absorption with increasing ZnO content and a shift of the absorption edge, suggesting changes in band gap energy and particle characteristics; the estimated band gap values reported from Tauc plots are 4.1 eV and 2.85 eV for the prepared ZnO-SiO? systems. FTIR spectra exhibit characteristic vibrations corresponding to Zn-O and Si-O-Si/Si-O stretching modes, supporting the coexistence of ZnO and silica networks within the composite. SEM observations show nanoscale particles with some aggregation, with particle sizes typically in the ~50-100 nm range.