Constructing of ultrathin Bi2WO6/BiOCl nanosheets with oxygen vacancies for photocatalytic oxidation of cyclohexane with air in solvent-free

Photocatalytic oxidation of cyclohexane (CHA) with air in solvent-free is an efficient and green approach for the production of cyclohexanol and cyclohexanone (KA oil). In the present work, ultrathin Bi2WO6/BiOCl heterojunction nanosheets are prepared by varying the amounts of potassium chloride (KCl) via a one-step solvothermal method. The oxygen vacancies (OV) in Bi2WO6/BiOCl nanosheets can be produced in situ during the photocatalysis. An efficient and selective photo-oxidation of CHA to KA oil with air as an oxidant in solvent-free was achieved over OV-Bi2WO6/BiOCl catalyst. The composition, structure, morphology, as well as textural, optical, and electrochemical properties of the photocatalysts are systematically analyzed by various characterization techniques. The photocatalytic activity (KA oil, 484.4 mu mol) for the titled reaction was significantly improved over OV-Bi2WO6/BiOCl with 1.8 and 9.8 times compared with that by pure BiOCl and Bi2WO6 catalysts, respectively. Meanwhile, up to 92.5% selectivity of KA oil and 5 cycles without photocatalytic activity loss were achieved. The photogenerated holes (h(+)) and center dot OH radicals are verified to be predominant reactive species by trapping experiments and electron paramagnetic resonance (EPR) tests. The excellent photocatalytic performance can be attributed to the enhanced photo-absorption, abundant oxygen vacancies, high exposure of active facets, and efficient electron-hole separation. Thereby, the present work offers a prospective strategy for constructing Bi-based photocatalyst with highly efficient and selective photocatalytic oxidation of CHA.