Abstract:
Flame spray pyrolysis (FSP) is a versatile, rapid, and scalable preparation technique for the nanocatalysts. CeO
2 and Pt-CeO
2 carriers, Pd-Pt-CeO
2 catalyst were synthesized by flame spray pyrolysis, and then Pd-Pt bimetallic catalysts were prepared by impregnation method, and as-obtained Pd-Pt catalysts were tested in the methane combustion. The physicochemical properties of the catalysts were characterized by ICP, XRD, TEM, BET, H
2-TPR, XPS, and Raman. TEM results showed that Pd and Pt species were highly dispersed in CeO
2 carriers in Pd-Pt/CeO
2 catalysts. Compared with the Pd-Pt-CeO
2(OS-FSP) catalyst prepared by one-step flame spray pyrolysis, the catalytic activity of the Pd-Pt/CeO
2(0.25)-WI prepared by co-impregnation was higher, with its
t50 reduced by 60 ℃, and no deactivation was seen for 60 h. It is attributed to the fact that the Pd-Pt/CeO
2(0.25)-WI catalyst has a higher molar ratio of Pd
0/Pd
2+ and Ce
3+/Ce
4+ on the surface of the catalyst and more lattice oxygen, resulting in an excellent performance during the methane combustion.