November 6, 2012
Speaker: Donald McGillivray, Materials Science MSc candidate, UOIT
Title: Synthesis of TiO2/CNTs Photocatalysts Using Supercritical CO2
Abstract: In this work titanium dioxide nanoparticles and rods were synthesized using supercritical carbon dioxide (SC-CO2) as the reaction medium. The syntheses were carried out in a high pressure system and ow cell designed and constructed for these studies. The system can reach temperatures and pressures well above the critical temperature and pressure of CO2, 31oC and 76.4 bars, respectively. TiO2 particles with different degree of crytallinity and morphology have been synthesized using acetic acid and titanium isopropoxide as precursors at pressures and temperatures up to 220 bars and 150oC, respectively. Materials were characterized using a number of analytical methods (XRD, TGA, SEM, Raman, and FTIR). Methylene blue was used to investigate the photocatalytic activity under UV irradiation and the results were compared with those obtained for two other commercial materials, Degussa P25 and anatase (25 nm) from Sigma-Aldrich. Future work will be also discussed.