Effects of reagents on the formation of nanoparticulate titanium dioxide synthesized by sol-gel technique

Abstract

Photocatalytic properties of titanium dioxide are generally enhanced through formation of nanometer-sized anatase Titanium dioxide (TiO2) phase but to achieve the desired chemical composition and particle size, appropriate selection of initial reagents are required. This study was conducted to examine the effects of the initial reagents, specifically titanium (IV) isopropoxide (TTIP), sub-micrometer-sized TiO2 dissolved in sulfuric acid (H2SO4), and TiO2 dissolved in H2SO4 with added polyacrylic acid, on the chemical compositions and particle sizes of the sol-gel synthesized TiO2 powder. Results indicated that synthesis of TiO2nano-particulates with the respective average sizes of 48 and 85 nm was achievable using TTIP or sub-micrometer-sized TiO2 dissolved in H2SO4 with added polyacrylic acid as initial reagents.. In the absence of polyacrylic acid, the formation of an additional secondary phase and the production of larger particles averaging 130 nm in size were observed. Results of the antibacterial test capability of the synthesized TiO2 also pointed out that powder synthesized from sub micrometer-sizedTiO2 dissolved in H2SO4 with polyacrylic acid added also proved that it is capable of reducing Staphylococcus aureus by more than 99.9%, suggesting that it could be a cost effective replacement for the more expensive TTIP reagent in the synthesis of the desired TiO2nano-particles.