Photocatalytic C-H bond activation by surface anchoring of [CoII(Saloph)(His)] complex on Ag-TiO2 nanocomposite

Abstract

A novel heterojunction plasmonic photocatalyst [Co(Saloph)(His)]/Ag-TiO2 as a nanohybrid material was applied for the photocatalytic activity towards the C-H bond cleavage of alcohols to the aldehyde using different oxidants, O2, H2O2, or TBHP under irradiation of visible-light and NHPI as cocatalyst. It was synthesized by photo-deposition of metallic silver nanoparticles on titanium oxide surface and follow it, modification with cobalt(II) Saloph complex under ultrasonic agitation condition using histidine linker to reach a photocatalyst under 50 nm in size and band gap 2.64 eV. The [Co(Saloph)(His)]/Ag-TiO2 nanohybrid was characterized with EDS, XRD, DRS, FT-IR, PL spectroscopies, FESEM imaging, and BET technique. The size This three-component plasmonic photocatalyst revealed high photocatalytic efficiency with 95% conversion and 99% selectivity in aerobic conditions. The higher photocatalytic performance of [Co(Saloph)(His)]/Ag-TiO2 than the Co(Saloph)/TiO2 and Ag-TiO2 NPs should be related to the localized surface plasmonic resonance (LSPR) of these motives. So, this three-component nanohybrid provides an efficient interfacial electron transfer process through a synergistic effect which allows producing a nanocatalyst, with advantages of stability and fast selective C-H bond activation of alcohols at ambient temperature using O2 as an inexpensive environmental friendly oxidant.