Unraveling the effect of alumina-supported Y- doped ceria composition and method of preparation on the WGS activity of gold catalysts.

The demands for high-purity hydrogen required in fuel-cell applications impose new goals and challenges for design of well performing water-gas shift (WGS) catalysts. Gold-based catalysts have exhibited high activity in the WGS reaction at low temperature. Preparation of appropriate and economically viable supports with complex composition by various synthesis procedures is an attractive approach to WGS performance improvement. The effect of two different preparation methods (wet impregnation or mechanical mixing) and ceria content (10, 20 or 30 wt%) on textural, structural, surface and reductive properties and WGS activity of gold catalysts was studied. Additionally, the role of Y 2 O 3 as a promoter of ceria was examined. Long-term stability test was carried out at 260 °C over the most active catalyst. The composition of the best performing sample (composed of about 70 wt% alumina), prepared by mechanical mixing, was considered promising in case of practical applications because of its cost efficiency. The combination of gold nanoparticles and alumina supported Y-doped ceria proved an advantageous approach for developing new catalytic formulations with high effectiveness in clean hydrogen production. Image 1 • Water-gas shift activity of gold catalysts on alumina-supported CeO 2 was studied. • The impact of supports composition (10, 20 and 30 wt% ceria) was investigated. • The effect of support preparation methods was analyzed. • The role of Y-doping of ceria on the WGS activity was examined. • Stability test over the best performing catalyst was carried out. [ABSTRACT FROM AUTHOR]