Photocatalytic Anaerobic Oxidation of Aromatic Alcohols Coupled With H2 Production Over CsPbBr3/GO-Pt Catalysts

Abstract

Metal halide perovskites (MHPs) have been widely investigated for various photocatalytic applications. However, the dual-functional reaction system integrated selective organic oxidation with H2 production over MHPs is rarely reported. Here, we demonstrate for the first time the selective oxidation of aromatic alcohols to aldehydes integrated with hydrogen (H2) evolution over Pt-decorated CsPbBr3. Especially, the functionalization of CsPbBr3 with graphene oxide (GO) further improves the photoactivity of the perovskite catalyst. The optimal amount of CsPbBr3/GO-Pt exhibits an H2 evolution rate of 1,060 μmol g−1 h−1 along with high selectivity (>99%) for benzyl aldehyde generation (1,050 μmol g−1 h−1) under visible light (λ > 400 nm), which is about five times higher than the CsPbBr3-Pt sample. The enhanced activity has been ascribed to two effects induced by the introduction of GO: 1) GO displays a structure-directing role, decreasing the particle size of CsPbBr3 and 2) GO and Pt act as electron reservoirs, extracting the photogenerated electrons and prohibiting the recombination of the electron–hole pairs. This study opens new avenues to utilize metal halide perovskites as dual-functional photocatalysts to perform selective organic transformations and solar fuel production.

Photocatalytic Anaerobic Dehydrogenation of Alcohols over Metal Halide Perovskites: A New Acid-Free Scheme for H2 Production

“…After the illumination by visible light, the EPR spectra of MAPbBr 3 -Pt and MAPB/rGO-Pt both display six characteristic signal peaks with a similar position. The nitrogen hyperfine splitting (α N ) and hydrogen hyperfine splitting (α H ) can match well with the simulated EPR spectra of DMPO–CH­(OH)­Ph, , as shown in Figure b. Thus, it can be proposed that the carbon-centered radical intermediate is the key radical species involved in the photocatalytic process.…”

Perovskite Cs3Bi2I9 Hexagonal Prisms with Ordered Geometry for Enhanced Photocatalytic Hydrogen Evolution

“…In recent years, various strategies have been adopted, including loading with cocatalysts, − constructing heterojunctions, − and doping with foreign elements, ,, all of which aim to promote efficient photogenerated hole and electron separation. Until now, to the best of our knowledge, there have been no reports aimed at controlling charge separation in MHP photocatalysts through morphology-control and facet regulation (i.e., through facet-specific charge migration).…”

Crystal phase engineering of Ru for simultaneous selective photocatalytic oxidations and H2 production

“…36 The diminished PL intensity of Ru/TiO 2 composites as compared with TiO 2 confirms that the decoration of Ru NPs enhances electron hole separation and reduces the radiative charge carrier recombination. 9 This is ascribed to the formation of the Schottky barrier at the Ru/TiO 2 interface, 39 with Ru acting as an electron sink, as depicted in Fig. 4.…”