Synthesis of zinc oxide nanostructures by calcination and solvothermal methods

This thesis includes a thorough examination into the synthesis and characterization of ZnO particles of various morphologies. The structure of the particles was analyzed by XRD, SEM, TEM, FTIR and XPS techniques and gas adsorption. XRD analysis confirmed the formation of wurtzite crystals, and microscopy images demonstrated their growth into various morphologies such as flower-like, nanorods, nanospheres, nanoprisms, and urchins. By XPS analysis, the oxygen defects on the particle surfaces were detected. The solvothermally produced nanospheres exhibited the highest mesopore surface area (30.56 m2/g), while calcined nanorods had the lowest (4.55 m2/g). The band gap energy (Eg) of the particles ranged between 3.08 and 3.29 eV and was lower than the theoretical value of wurtzite ZnO (3.37 eV). The photocatalytic degradation tests were carried out with methylene blue (MB) dye as the model organic pollutant. The results showed that calcined, acetic acid-modified nanorods were particularly ideal for photocatalytic degradation. Over the course of 24 h, 50.42 % of MB was degraded by these nanorods. Additionally, the thesis explored the preliminary experiments for the production and characterization of ZnO-PEG hybrids. FTIR spectra confirmed the interaction of PEG with ZnO on the particle surfaces. Their biocompatibility was qualitatively compared through immersion in simulated body fluid (SBF). Results revealed their potential to be used in the biomedical field.