Constructing electron transfer bridge of Pr doping MIL-125(Ti) for high-efficient photoreduction CO2

Abstract

MIL-125(Ti) is well known for having stable structure, tunable electron structure, and multiple active sites, which is commonly studied in the field of photocatalysis. In this work, a series of rare earth (RE) doped MIL-125(Ti) (RE=Ce, Pr, Tm, Dy, Eu, and Sm) are prepared via the one-step hydrothermal method. Notably, Pr-MIL-125 displays a significantly enhanced catalytic performance than other RE-doped MIL-125, resulting in a maximal CO and CH4 yield of 13.30 and 0.87 µmol·g−1·h−1, respectively, which are 2.53-fold and 4.14-fold of the pristine MIL-125. The layered morphology endows Pr-MIL-125 with more active sites and facilitates the reaction of photoreduction CO2. Furthermore, the promoted photoactivities attributed to Pr ion dopant can act as electron transfer bridge and suppress charge recombination. This work would provide insight and guidance for designing RE-MOF based photocatalysts and enhancing the performance of photoreduction CO2.