Effect of varying laser fluence on physicochemical characteristics of titania nanoclusters grown via pulse laser ablation in liquid approach

Abstract Commercial scale production of stable titania nanoclusters (TiO 2 NCs) with controlled physicochemical properties remains challenging. Over the years, to meet the constant industrial demand of different types of pure TiO 2 NCs with desired size distribution various strategies have been developed. Most of the existing synthesis protocols are not enviro-friendly and often require different chemical precursors. Considering these factors, we used the eco-friendly pulse laser ablation in liquid (PLAL) method to make five colloidal suspensions of TiO 2 NCs in deionized water (DIW). The values of laser fluence (LF) were varied (4.5, 6.8, 9.1, 11.3, and 13.6 J.cm −2 ) to determine their influence on the structural, morphological, and absorption properties of the produced samples. To ablate the solid pure target of titania, the Nd-YAG laser pulse at various LFs, constant wavelength, fixed repetition rate and constant pulse period was employed. The TEM evidenced the nucleation of the highly spherical crystalline colloidal suspension of the optimum TiO 2 NCs sample. TiO 2 NCs grown at LF of 9.1 J cm −2 revealed the best size distribution with mean size of 13.59 ± 4.68 nm. The EDX spectrum of the optimum sample manifested their respective atomic compositions. Both XRD and FTIR analysis confirmed nanocrystallinity and high purity of the obtained specimens. UV-Vis absorption spectra showed the band-to-band absorption peak characteristic of 278 to 290 nm and a sharp UV absorbance edge, with blue-shifted. The zeta potential values of all samples were measured to evaluate their long-term stability. In short, the variation of LF had significant impact of overall attributes of the colloidal TiO 2 NCs. It was shown that by adjusting the LF, the physicochemical properties of the products can be controlled, thus contributing towards sustainable production of TiO 2 NCs required for diverse practical applications.