In situ redispersion of rhodium nanocatalyst for CO2 reforming of CH4

Noble metal nanoparticles (NPs) exhibit high reactivity towards hydrocarbon reforming, however, suffer from agglomeration and poisoning issues (e.g., carbon deposition). A facile and environmental approach to rejuvenate noble metal catalysts is techniques using thermal redox cycles. Here we demonstrate that in situ thermal oxidative aging and reduction strategy can reverse the sintering of Rh/TiO2 catalyst and meanwhile this redox process significantly affects the catalytic performance towards methane dry reforming (DRM). The oxidative aging process has substantial impact on the mobilization of Rh species across TiO2, and thus the degree of oxymetal activation and the Rh NPs size. In the subsequent reductive process, reduction temperature not only influences oxymetal activation but also the electronic structure of Rh NPs, which directly relates to the carbon formation.

Automated summary

The study demonstrates that thermal oxidative aging and reduction strategy can reverse the sintering of Rh/TiO2 catalyst and significantly affect the catalytic performance towards methane dry reforming. The oxidative aging process impacts the mobilization of Rh species across TiO2, while reduction temperature influences oxymetal activation and electronic structure of Rh NPs, associated with carbon formation.