Highly Photoactive Titanium Dioxide Supported Platinum Catalyst: Synthesis Using Cleaner Ultrasound Approach.

Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a vital role in catalytic activity. The noble metals such as platinum (Pt) and gold (Au) are expensive; despite this, they have proven their existence in catalysis, motivating the synthesis of supported metal catalysts. Metal catalysts need to be highly dispersed onto the support. In this investigation, an ultrasound approach has been attempted to synthesise highly photoactive titanium dioxide (TiO₂) nanoparticles by the hydrolysis of titanium tetraisopropoxide in an acetone/methanol mixture. To enhance its photocatalytic activity, TiO₂ was doped with Pt. The synthesised photocatalyst was characterised by techniques such as particle size analysis (PSA), XRD, FE-SEM, TEM, and EDX. The enhancement in the surface characteristics of Pt-doped TiO₂ compared with bare TiO₂ support was confirmed with Brunauer–Emmett–Teller (BET) analysis. The enhanced surface area and uniformity in particle size distribution at the nanoscale level were due to the effects of ultrasonic irradiation. The obtained results corroborated the size and composition of the synthesised catalysts. The size of the catalysts is in the nanometre range, and good dispersion of Pt catalysts over the TiO₂ support was observed. The UV-Visible spectroscopy analysis was performed to study the optical properties of the synthesised TiO₂ and Pt/TiO₂ photocatalysts. An increase in the absorbance was noted when Pt was added to TiO₂, which is due to the decrease in the band gap energy. [ABSTRACT FROM AUTHOR]