Influence of the triblock copolymer P123 and phosphorous on the physico-chemical properties of TiO2

Abstract Nanocrystalline TiO 2 powders with a high specific surface area (up to 335 m 2 /g) were synthesized by a combination of sol–gel and solvothermal syntheses. The influence of the TiO 2 framework template, the triblock copolymer P123, and the framework stabilizer, phosphorous (P) in the form of phosphoric acid (H 3 PO 4 ), on the photocatalytic oxidation of isopropanol was studied. As-prepared samples were characterized by means of X-ray powder diffraction (XRD), thermogravimetric analysis (TG-DTA), measurements of the specific surface area ( s BET ), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The photocatalytic activity under UV (ultraviolet) irradiation of the as-prepared samples was measured by monitoring the degradation of the isopropanol in the gaseous medium. The application of P123 increased the specific surface area of the samples; furthermore, the addition of phosphorous inhibited the particle growth during the thermal treatment and stabilized the anatase crystal phase at higher annealing temperatures (up to 900 °C), thus leading to a higher photocatalytic activity. However, when P123 and phosphorous were used together the specific surface area was increased and an improvement in the photocatalytic oxidation was observed.