A Supported Bismuth Halide Perovskite Photocatalyst for Selective Aliphatic and Aromatic C-H Bond Activation.

ABSTRACT: Direct selective oxidation of hydrocarbons to oxygenates by O₂ is challenging. Catalysts are limited by the low activity and narrow application scope, and the main focus is on active C-H bonds at benzylic positions. In this work, stable, lead-free, Cs₃ Bi₂ Br₉ halide perovskites are integrated within the pore channels of mesoporous SBA-15 silica and demonstrate their photocatalytic potentials for C-H bond activation. The composite photocatalysts can effectively oxidize hydrocarbons (C₅ to C₁₆ including aromatic and aliphatic alkanes) with a conversion rate up to 32900??mol?g_cat ^-1 ?h^-1 and excellent selectivity (>99?%) towards aldehydes and ketones under visible-light irradiation. Isotopic labeling, in?situ spectroscopic studies, and DFT calculations reveal that well-dispersed small perovskite nanoparticles (2-5?nm) possess enhanced electron-hole separation and a close contact with hydrocarbons that facilitates C(sp³ )-H bond activation by photoinduced charges.

SUBMITTER: Dai Y 

PROVIDER: S-EPMC7154683 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature