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چکیده
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A new nanohybrid catalyst by covalent linking of tetraacetate porphyrin cobalt(II) complex to TiO2/BiVO4 nanocomposite was synthesised and its photocatalytic efficiency toward alcohol oxidation under visible light irradiation monitored by GC. This nanohybrid materials as implement photocatalyst was characterized by physicochemical techniques FESEM imaging, EDS, XRD, DRS, BET and FT-IR spectroscopy. Also its role as photocatalyst evaluated with mechanismetic approach in aerobic condition by changing several parameters such as solvent, substrate, oxidant, catalysts amount, reaction temperature and ratio of oxidant to substrate. The photocatalytic activity of this nanohybrid catalyst with average size 24 nm increased almost twice compared to TiO2/BiVO4 nanocomposite from 35% to 85% conversion while the selectivity was 99%. A plausible mechanism was proposed. In fact, the cobalt porphyrin complex as a light sensitizer improves the photocatalytic activity by impregnation onto the TiO2 surface. The photocatalyst was reused for several times without significant loss of activity. So, this nanohybrid robust catalyst has excellent advantages such as facile synthesis, high activity and selectivity using O2 and other environmental friendly oxidants in mild condition toward aldehyde production.
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