Photocatalytic aerobic oxidation by using oxygen molecules (O2) as green and low-cost oxidants is of great attraction, where the introduction of irradiation has been proved as an efficient strategy to lower reaction temperature as well as promote catalytic performance. Moreover, the oxygen vacancies (OVs) of catalyst are highly active sites to adsorb and activate O2 during photocatalytic aerobic oxidation. However, OVs are easily blocked by oxygen atoms from active oxygen species during the catalytic process, leading to the deactivation of catalysis. Herein, a promising catalyst toward photocatalytic aerobic oxidation was successfully developed by recovering the OVs through doping Au atoms into Ti3C2Tx MXene (Au/Ti3C2Tx). Impressively, Au/Ti3C2Tx exhibited remarkable activity under full-spectrum irradiation towards photooxidation of methyl phenyl sulfide (MPS) and methylene blue (MB), attaining a conversion of >90% at room temperature. Moreover, Au/Ti 3C2Tx also manifested remarkable stability by maintaining >95% initial activity after 10 successive reaction rounds. Further mechanistic studies indicated that the OVs of Au/Ti 3C2Tx served as the active centers to efficiently adsorb and activate O2. More importantly, the doped Au atoms of Au/Ti3C2Tx were conducive to the recovery of OVs during photocatalytic process from the results of theoretical and experimental aspects. The recovered OVs of Au/Ti3C2Tx continuously and efficiently activated O2, directly contributing to the remarkable catalytic activity and stability.
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Article type
Year
Research Article
Issue
Nano Research 2022, 15(4): 2862-2869
Published: 20 October 2021
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