Investigating the combined effects of synthesis parameters on Ta2O5 nanoparticles via sol-gel method

The sol-gel method proposes precise control over Tantalum pentoxide (Ta2O5) nanoparticle synthesis. However, few investigations have examined the effect of synthesis parameters on the final Ta2O5 nanoparticles produced using this method. This study aims for optimization of the sol-gel synthesis route of Ta2O5 by evaluating the impact of calcination temperature (400 °C and 800 °C), aging time (1 day and 7 days), and precursor concentration (0.5 g/20 mL and 0.75 g/20 mL) on the characteristics of the nanoparticles. The existence of Ta–O–Ta and Ta–O bonds was confirmed by FTIR, establishing the formation of Ta2O5. XRF revealed a composition of Ta2O5 of about 89%–94.8% with insignificant impurities. According to X-ray diffraction studies, nanoparticles' crystallinity increased with an increase in calcination temperature, an increase in aging time, and an increase in precursor concentration. From SEM results, it can be concluded that the aging time, precursor concentration, and calcination temperature play a profound role in the size and morphology of the nanoparticles, where longer aging times and higher temperatures gave rise to bigger and more aggregated particles. A significant influence of morphology at a higher precursor concentration at an aging time of 7 days was further evident. The analysis of the UV–Vis spectra and Tauc plots suggested that as the particle size and morphology change, the optical band gap decreases, corroborating literature values. The present work emphasized optimizing the sol-gel parameters to influence the size, morphology, and optical properties of Ta2O5 nanoparticles for impending applications.