A Comparative Study on the Structure and Catalytic Performance of UiO-66 Supported Pt Nanocatalysts Prepared by NaBH4 and H2 Reduction: Light-Off, Durability and Mechanism for CO Oxidation

Metal–organic framework (MOF) supported nanocatalysts are attracting great attentions in heterogeneous catalysis. However, they are still less explored and poorly understood in catalyzing solid–gas reactions. In current work, two MOF supported Pt nanocatalysts were prepared by immersion method coupled with the most commonly used NaBH 4 (Pt/UiO-66-NaBH 4 ) and H 2 (Pt/UiO-66-H 2 ) reduction, and their catalytic CO oxidation performances were investigated. NaBH 4 and H 2 reduction both provide highly dispersed Pt/UiO-66 nanocatalysts, and the two prepared catalysts display excellent CO oxidation activities. Moreover, CO oxidation durability tests reveal that Pt/UiO-66-NaBH 4 shows superior durability and structure stability, which are much better than those of Pt/UiO-66-H 2 . The high structure stability of Pt/UiO-66-NaBH 4 also endows it with good H 2 O and CO 2 tolerance. This work attempts to elucidate the influence of reduction methods on the structures and catalytic CO oxidation performances of Pt/UiO-66 catalysts by employing XRD, TEM, N 2 -sorption, XPS and in situ DRIFTS techniques. Furthermore, the mechanism of CO oxidation was studied by in situ DRIFTS, and the result reveals that the CO oxidation on the two catalysts follows different mechanism.