Characterization of TiO2nanoparticles for nanomaterial applications: Crystallite size, microstrain and phase analysis using multiple techniques

This study aimed to verify the suitability of TiO2nanoparticles as nanomaterials in terms of crystallite size, microstrain and phase. The TiO2nanoparticles were tested experimentally in suspensions of mono ethylene glycol and distilled water (MEG-DW) at ratios of 10:90, 25:75, and 40:60. The nanoparticles were dispersed in the base liquid via a two-step process, resulting in the formation of TiO2-3%/MEG-10, TiO2-3%/MEG-25, and TiO2-3%/MEG-40 nanofluids. The results revealed average crystallite sizes of approximately 20.10, 22.10, and 39.6 nm for the three nanofluid samples, as determined by the Scherrer equation, Williamson–Hall (W–H) plot, and TEM-ImageJ software. These results confirm that the TiO2nanoparticles meet the nanomaterial criteria with a sub-100 nm size. The microstrain analysis yielded values of 0.000020, 0.000299, and 0.001386 for the three samples and further investigation confirmed the presence of rutile. The high-temperature stability of the rutile phase makes the TiO2nanofluids suitable for use in industrial heating systems.