Singlet Oxygen-Engaged Selective Photo-Oxidation over Pt Nanocrystals/Porphyrinic MOF: The Roles of Photothermal Effect and Pt Electronic State

Abstract

The selectivity control toward aldehyde in the aromatic alcohol oxidation remains a grand challenge using molecular oxygen under mild conditions. In this work, we designed and synthesized Pt/PCN-224(M) composites by integration of Pt nanocrystals and porphyrinic metal-organic frameworks (MOFs), PCN-224(M). The composites exhibit excellent catalytic performance in the photo-oxidation of aromatic alcohols by 1 atm O₂ at ambient temperature, based on a synergetic photothermal effect and singlet oxygen production. Additionally, in opposition to the function of the Schottky junction, injection of hot electrons from plasmonic Pt into PCN-224(M) would lower the electron density of the Pt surface, which thus is tailorable for the optimized catalytic performance via the competition between the Schottky junction and the plasmonic effect by altering the light intensity. To the best of our knowledge, this is not only an unprecedented report on singlet oxygen-engaged selective oxidation of aromatic alcohols to aldehydes but also the first report on photothermal effect of MOFs.