Synergistic Effect of Photocatalyst CdS and Thermalcatalyst Cr₂O₃-Al₂O₃ for Selective Oxidation of Aromatic Alcohols into Corresponding Aldehydes

Abstract

Selective transformation of alcohols to corresponding aldehydes has a crucial significance under mild conditions in industrial manufacturing. Herein, a novel photothermal catalyst (Cr 2 O 3 -Al 2 O 3 )/ CdS (CAO/CdS) was successfully synthesized by coupling twodimensional Cr 2 O 3 -Al 2 O 3 (CAO) nanosheets and one-dimensional CdS nanorods. The CAO/CdS was characterized in detail. The synergistic effect of thermal catalyst CAO and photocatalyst CdS on the transformation of aromatic alcohols into aldehydes was verified. The result exhibited that alcohols could be oxidized into corresponding aldehydes efficiently under visible light illumination due to photocatalysis of CdS and thermal catalysis of CAO. CAO can weaken the bonds of O−H and C−Hα of alcohol at low temperatures, and CdS can produce active substances (•O 2 − and h + ) for oxidizing alcohols to aldehydes under visible light illumination. The benzaldehyde yield increased about three times. It is proposed that the work has significant theoretical and practical values in photocatalysis studies.

Photocatalytic Performance of NiS/CdS Composite with Multistage Structure

“…have low photocatalytic efficiency, and conventional modification and optimization cannot significantly improve the activity. Metal sulfides (e.g., CdS, MoS 2 , and CdIn 2 S 4 ) have unique electronic structures and excellent optical properties, performing great applications in photocatalytic degradation, selective oxidation, hydrogen production, and CO 2 reduction. − Particularly, CdS as an important photocatalytic material has been intensively studied as it has relatively narrow band gap (2.4 eV) and easily regulated surface structure . Notably, CdS possesses a more negative conduction band than H 2 /H 2 O potential, which facilitates the reduction reaction (e.g., H 2 production).…”

One-step conversion of lignin-derived alkylphenols to light arenes by co-breaking of C–O and C–C bonds

“…S5, ESI†). All catalysts showed the characteristic peaks of γ-Al 2 O 3 (JCPDS 47-1308) at 37.3°, 45.8° and 67.3° 25–28 (Fig. 4), indicating that the catalysts prepared by the incipient wetness impregnation method did not change the crystal structure of the support γ-Al 2 O 3 .…”

Polyoxometalate‐Based Metal Organic Frameworks: Recent Advances and Challenges

“…The catalytic oxidation of alcohols as an important functional group transformation has received extra attention from organic synthetic chemists [34] . It is also a major process for the synthesis of carbonyl compounds in fine chemistry, of which the oxidation of aromatic alcohols is a central component [35] . In recent years, scientists have devoted themselves to developing some simple and efficient methods to selectively oxidize alcohols to ketones [36–40] .…”