The effect of La on Au-ceria catalyst for water gas shift reaction

Abstract

For Au-ceria catalysts prepared by deposition-precipitation method, catalytic performance of water gas shift reaction was studied in different La loadings. In the complete doping range, ceria retains with its cubic fluorite structures. BET, XRD, H 2 -TPR, HRTEM studies showed that La doping can improve the activity of Au-ceria catalyst by stabilizing ceria and modifying its morphology. In addition, the test of catalyst stability evaluation also proved a better stability performance of Au-ceria catalyst can be realized by appropriate La doping.

Effect of La2O3 on Ru/CeO2-La2O3 Catalyst for Ammonia Synthesis

“…That is to say, it could be reasonable to assume that the hydrogen consumption is determined by the reduction extent of ceria for the catalysts. From Table 3, hydrogen consumption of La doping catalysts is much higher than that of Ru/CeO 2 , indicating that La doping could promote the reduction of ceria, which is good accordance with the predecessors' studies [17]. Figure 6 represent the XPS spectra of Ru/CeO 2 and Ru/ CeO 2 -10La catalysts at Ce 3d.…”

“…CeO 2 and La doping CeO 2 have two peaks at 200-400 and 400-650°C from ambient temperature to 750°C, respectively. These peaks usually were assigned to the reduction of the surface oxygen and sub-surface oxygen of ceria and mixed oxides [17].…”

“…could significantly increase the number of oxygen vacancy of CeO 2 [15], Sanchez and Gazquez [16] proposed that oxygen vacancies in the fluorite oxide structure can change the dispersion of the supported metal. Furthermore, Zhang [17] had found that certain dopants, such as lanthanum, could facilitate the reduction of cerium oxide.…”

Water–Gas Shift Reaction over CuO/CeO2 Catalysts: Effect of the Thermal Stability and Oxygen Vacancies of CeO2 Supports Previously Prepared by Different Methods

“…Thereinto, many scientists have paid attention to the ceria loaded with precious metals (Pt, Pd and Rh) [6][7][8], especially gold [9][10][11]. The effect of La as additive on the catalytic performance of Au-ceria WGS catalyst was then studied by our group [12]. However, due to the high cost of the above precious metals and/or their instability, more and more attention has been focused on the cheap transition metals, especially the ceria-supported copper catalysts that have been found to show high catalytic activity for the WGS reaction and are expected to substitute for the noble metal catalysts in the future [13][14][15].…”

Hydrogen production by steam reforming of ethanol over Co3O4/La2O3/CeO2 catalysts synthesized by one-step polymerization method

“…3a shows the TPR profile of the CeO 2 , Ce 4 La, Ce 8 La and Ce 12 La supports, where it can be observed that the reduction peak located at 550 • C in CeO 2 (peak related to surface-capping oxygen of CeO 2 ) is shifted to lower temperature, after addition of La 2 O 3 . This finding suggests that this displacement is due to the solid solution Ce(La)O x formed [58,61,28].…”