Structure-activity relationship in water-gas shift reaction over gold catalysts supported on Y-doped ceria
来源期刊：Journal of Rare Earths2019年第4期
论文作者：Tatyana Tabakova Lyuba Ilieva Ivan Ivanov Maela Manzoli Rodolfo Zanella Petya Petrova Zbigniew Kaszkur
文章页码：383 - 392
摘 要：The utilization of pure hydrogen as an energy source in fuel cells gave rise to renewed interest in developing active and stable water-gas shift catalysts. Gold catalysts have proven to be very efficient for water-gas shift reaction at low temperature. The aim of the present study was to investigate the effect of:（i） different preparation methods（impregnation and coprecipitation） to obtain a modified ceria support,and（ii） the amount of Y2 O3（1.0 wt%, 2.5 wt%, 5.0 wt% and 7.5 wt%） as dopant on the water-gas shift activity of Au/CeO2 catalysts. An extended characterization by means of SBET, XRD, HRTEM/HAADF, FTIR,H2-TPR and CO-TPR measurements in combination with careful evaluation of the catalyst behavior allowed to shed light on the parameters governing the water-gas shift activity. The catalysts show very high activity（>90% CO conversion） in the temperature range 180-220 ℃,with a slightly better performance of the gold catalysts on supports prepared by impregnation. The decreased activity with increasing Y2 O3 concentration is related to the hindering of oxygen mobility due to ordering of surface oxygen vacancies in vicinity of segregated Y3+. The effect of catalyst pre-treatments and the stability of the best performing samples were examined as well.
Tatyana Tabakova1，Lyuba Ilieva1，Ivan Ivanov1，Maela Manzoli2，Rodolfo Zanella3，Petya Petrova1，Zbigniew Kaszkur4
1. Institute of Catalysis, Bulgarian Academy of Sciences2. Department of Drug Science and Technology & Centre for Nanostructured Interfaces and Surfaces, University of Turin3. Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico4. Institute of Physical Chemistry,PAS
摘 要：The utilization of pure hydrogen as an energy source in fuel cells gave rise to renewed interest in developing active and stable water-gas shift catalysts. Gold catalysts have proven to be very efficient for water-gas shift reaction at low temperature. The aim of the present study was to investigate the effect of:（i） different preparation methods（impregnation and coprecipitation） to obtain a modified ceria support,and（ii） the amount of Y2 O3（1.0 wt%, 2.5 wt%, 5.0 wt% and 7.5 wt%） as dopant on the water-gas shift activity of Au/CeO2 catalysts. An extended characterization by means of SBET, XRD, HRTEM/HAADF, FTIR,H2-TPR and CO-TPR measurements in combination with careful evaluation of the catalyst behavior allowed to shed light on the parameters governing the water-gas shift activity. The catalysts show very high activity（>90% CO conversion） in the temperature range 180-220 ℃,with a slightly better performance of the gold catalysts on supports prepared by impregnation. The decreased activity with increasing Y2 O3 concentration is related to the hindering of oxygen mobility due to ordering of surface oxygen vacancies in vicinity of segregated Y3+. The effect of catalyst pre-treatments and the stability of the best performing samples were examined as well.
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