Mesoporous CdS-sensitized TiO2 nanoparticle assemblies with enhanced photocatalytic properties: Selective aerobic oxidation of benzyl alcohols

• Mesoporous CdS-sensitized TiO2 nanoparticle assemblies were prepared.
• CdS-MTA is efficient catalyst for the aerobic oxidation of aromatic alcohols.
• These mesophases show superior photocatalytic activity and selectivity.
• Synthesis of corresponding aryl ketones in high chemical yields was attained.

Mesoporous TiO2-based semiconductors with visible-light response are promising materials for photocatalytic and photoelectrochemistry applications. In this work, we have used surfactant-assisted aggregating assembly of CdS and TiO2 nanocrystals to assemble mesoporous binary CdS-TiO2 heterostructure. The product features a three-dimensional network of interconnected CdS quantum dots and anatase TiO2 nanoparticles and exhibits large internal BET surface area (157 m2 g−1) and uniform pores (ca. 7.5 nm). Catalytic experiments showed an exceptionally high catalytic activity of these mesophases under UV–visible light oxidation of various para-substituted aryl alcohols, using molecular oxygen as oxidant. Moreover, product analysis and kinetic results indicated that these photooxidation reactions proceed via an electron transfer route from alcohol substrate to the excited states of the catalyst.

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