Hybridizing strategy of decatungstate by Au nanoparticles for enhanced photo-catalytic oxidation of hydrocarbons by dioxygens

• Published in: Applied catalysis. A, General General, 2022-01, Vol.630, p.118473, Article 118473
• Main Authors: Yang, Bo, Zhu, Jiekun, Hu, Siqing, Deng, Youer, Luo, Mingyu, She, Jialuo, Liu, Yachun, Zhang, Chao, Tang, Senpei, Fu, Zaihui
• Format: Article
• Language: English
• Subjects: Acetophenone; Au nanoparticles; Catalytic oxidation; Decatungstate; Electron transport; Ethylbenzene; Gold; Hydrocarbons; Molecular oxygen; Nanoparticles; Oxidation; Photo-catalytic oxidation; Regeneration; Selectivity
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2021.118473

Decatungstate (DT) is very potential photo-catalyst for the dioxygens (O2)-based selective oxidation but still needs to be improved in photo-catalytic efficiency and regeneration. This paper discloses that Au nanoparticles (NPs)-loaded DT (Au/DT) is conveniently synthesized via the reduction of chloroauric acids introduced in the synthesis of DT. A series of characterizations and quenching tests support that the doped Au NPs can remarkably improve the visible-light- harvesting and photo-excited quantum efficiencies of DT, and as the excellent electronic transport carriers, they also plays an additional role in converting O2 into the active superoxide (•O2-) anion radical. As a result, the suggested Au/DT exhibits a significantly enhanced photo-catalytic efficiency for the visible-light-triggered selective oxidation of inert hydrocarbons under 25–28 °C and 1 atm pure O2 atmosphere. Under optimized conditions, the best 1%Au/DT achieves 64.2% conversion and 93% acetophenone selectivity in the photo-oxidation of ethylbenzene and it has an outstanding regeneration ability. The hybridizing engineering (HE) strategy of Au NPs doping can improve DT’s visible light harvesting efficiency and redox capacity via lowering frontier orbital energy levels, and in which Au NPs as the excellent electronic transport carriers also hoist DT’s photo-excited quantum efficiency and the reactivity of O2 in the visible light-driven selective oxidation of inert hydrocarbons. [Display omitted] •Firstly realizing the doping of Au NPs in the cage of non-lacunary decatungstate (DT).•Doped Au NPs remarkably improve DT’s photo-physiochemical and redox properties.•Doped Au NPs play a crucial role in converting O2 into active •O2- anion radical.•Au/DT possesses significantly enhanced visible-light-catalytic performance.•Au/DT has a good application potential in photo-catalytic oxidation of hydrocarbons.