Comprehensive evaluation of TiO2 nanofluid stability: Insights from pH, EC measurements, and UV-Vis spectroscopy

This study delves into assessing the stability of different nanofluids containing TiO₂ nanoparticles, employing either ethylene glycol (EG) or water as the base fluid. The results obtained will be applied to photovoltaic panels in future work, in particular to solve the cooling problems facing these systems, in order to improve their efficiency and durability. The nanoparticles, approximately 75 nm in size as determined by the Debye-Scherrer equation and X-ray diffraction (XRD), were utilized to formulate nanofluids at concentrations of 0.1 %, 0.3 %, and 0.5 % using a two-step method. To gauge the stability of these prepared nanofluids, practical investigations were conducted involving pH and electrical conductivity (EC) measurements, along with UV-Vis spectroscopy spanning the wavelength range of 200–800 nm. The findings reveal that nanofluids with 0.1 % and 0.5 % TiO₂ in water demonstrated promising stability. Moreover, the absorbance levels of nanofluids containing 0.1 %, 0.3 %, and 0.5 % TiO₂ in EG, as well as 0.3 % TiO₂ in water, decreased with increasing settling time, as observed through UV-Vis spectroscopy analysis, consistent with prior research. Additionally, the study of pH and EC stability for 0.5 % TiO₂ in water indicated satisfactory results.