275786 Ultrasonic Spray Pyrolysis Synthesis of Ag-TiO2 Nanocomposite Photocatalysts for Simultaneous H2 Production and CO2 Reduction

Tuesday, October 30, 2012
Hall B (Convention Center )
Cunyu Zhao and Ying Li, University of Wisconsin-Milwaukee, Milwaukee, WI

Simultaneous photocatalytic hydrogen production and CO2 reduction (to form CO and CH4) from water using methanol as a hole scavenger were investigated using silver-modified TiO2 (Ag/TiO2) nanocomposite catalysts. A simple ultrasonic spray pyrolysis (SP) method was used to prepare mesoporous Ag/TiO2 composite particles using TiO2 (P25) and AgNO3 as the precursors. The material properties and photocatalytic activities were compared with those prepared by a conventional wet-impregnation (WI) method. It was found that the samples prepared by the SP method had a larger specific surface area and a better dispersion of Ag nanoparticles on TiO2 than those prepared by the WI method, and as a result, the SP samples showed much higher photocatalytic activities toward H2 production and CO2 reduction. The optimal Ag concentration on TiO2 was found to be 2 wt%. The H2 production rate of the 2% Ag/TiO2-SP sample exhibited a six-fold enhancement compared with the 2% Ag/TiO2-WI sample and a sixty-fold enhancement compared with bare TiO2. The molar ratio of H2 and CO in the final products can be tuned in the range from 2 to 10 by varying the reaction gas composition, suggesting a viable way of producing syngas (a mixture of H2 and CO) from CO2 and water using the prepared Ag/TiO2 catalysts with energy input from the sun.

Extended Abstract: File Not Uploaded
See more of this Session: Poster Session: Nanoscale Science and Engineering
See more of this Group/Topical: Nanoscale Science and Engineering Forum