Photothermal synergy of 1D Cd0.9Zn0.1S and 3D Mn3O4 for achieving forcefully active and highly selective aromatic alcohol oxidation

Constructing photothermal catalysts is a promising strategy to improve the efficiency of selective photocatalytic oxidation of aromatic alcohol to aromatic aldehyde. Herein, Mn3O4/Cd0.9Zn0.1S (CZS) photothermal catalysts have been prepared by introducing an as-prepared CZS photocatalyst during Mn3O4 preparation. The Mn3O4/ CZS samples exhibit higher catalytic performance for selective oxidation (SO) of aromatic alcohol. Especially, the optimized 10% Mn3O4/CZS sample possesses 7 times yield of CZS with an over 90% selectivity. The photo-thermal synergetic catalytic mechanism of Mn3O4/CZS for the SO of aromatic alcohol was proposed. Mn3O4(2MnO center dot MnO2) severs as the center of thermal catalysis and O-2 adsorption. The high-valent MnO2 oxidized aromatic alcohols into aromatic aldehydes and the generated low-valent MnO was oxidized to MnO2 by adsorbed O-2, forming a thermal cycling reaction. Meanwhile, the photoexcited electrons (e(-)) originating from CZS were transferred to Mn(3)O(4 )due to the matching energy level of MnO and CZS and further reduced the adsorbed O-2 to active oxygen (center dot O-2(-)) and lattice oxygen (O-2(-)), availably accelerating the separation of photoexcited carriers. Finally, center dot O-2(-), O2- and photoexcited holes (h(+)) can also selectively oxidize aromatic alcohol. This study provides an alternative paradigm for the efficient SO of aromatic alcohol.

Automated summary

The Mn3O4/CZS photothermal catalysts show enhanced catalytic performance for the selective oxidation of aromatic alcohol, with high selectivity and yield. This study proposes a photo-thermal synergetic catalytic mechanism for the efficient selective oxidation of aromatic alcohol.