Gold supported on mesoporous titania thin films for application in microstructured reactors in low-temperature water-gas shift reaction

Au (1 wt.%)/TiO2 catalytic thin films were prepared on a surface-modified titanium substrate for application in a water-gas shift (WGS) microstructured reactor. Au-containing mesoporous titania films were synthesized using Pluronic 127 surfactant as a structure directing agent and titanium tetrabutoxide as titania source. Colloidal gold nanoparticles of 4 nm diameter were added to the synthesis sol prior to spin-coating. The resulting thin films were characterized by X-ray diffraction, transmission electron microscopy, ethanol adsorption–desorption isotherms and spectroscopic ellipsometry. Catalytic activity and selectivity were measured for the WGS reaction at temperatures between 220 and 290 °C. The reaction rate measured at CO conversions of below 10% was similar to that reported for gold supported on mesoporous titania and on ceria modified mesoporous titania pelletized catalysts prepared via deposition–precipitation