Effect of Growth Time on Structural and Optical Properties of Chemically Synthesized TiO2 Nanostructures

Introduction: Titanium Dioxide (TiO2) is popular in the scientific community due to its wide variety of applications in optoelectronic devices, solar cells, gas sensors, photocatalytic reagents, and the biomedical industry. It is a wide band gap semiconductor with a band gap of 3.2eV. Usually, it shows three different phases, like anatase, rutile, and brookite, based on the synthesis method and annealing temperature. Method: Here, we report a simple chemical process to synthesize TiO2 nanostructures (NSs) at low temperatures to study the impact of growth time on structural and morphological properties. During synthesis, we permitted the samples to grow for 5 hr (sample-T5) and 7 hr (sample-T7) and continued the stirring process accordingly. We performed XRD, UV-Vis, and FESEM analysis with the samples. Result: XRD confirmed the effect of growth time on the size of the structures, and a shift in the absorption edge was observed in UV-Vis spectra, which indicated a change in the band gap. FESEM confirmed the change in nanostructures' size in both samples. Conclusion: The tuning in band gap due to growth time variation may be an interesting phenomenon to explore for modern scientific applications.