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Bio-based substances (BBS) isolated from urban biowaste have been employed to prepare hybrid magnetic nanomaterials with iron oxides. Such materials have been tested, in the presence of hydrogen peroxide, for the light induced photodegradation of four microcontaminants (MCs) in aqueous environment: Carbamazepine (C, an anticonvulsant and analgesic drug), Flumequine (F, an antibiotic), Ibuprofen (I, a non-steroidal anti-inflammatory drug), and Sulfamethoxazole (S, an antibiotic). Preliminary photodegradation experiments were carried out at lab-scale in a solar simulator, whereas optimized experiments were carried out in a pilot plant under natural solar radiation. The MCs complete abatement has been observed when working at acidic pH with no significant kinetic differences between experiments run in solar simulator and in the solar pilot plant

Graphitic carbon nitride assisted partial photocatalytic oxidation of 5-hydroxymethyl-2-furfural (HMF) in aqueous medium was investigated. Different carbon nitride precursors were considered, being melamine the one yielding the most efficient photocatalyst. The obtained 30% selectivity of HMF oxidation towards 2,5-furandicarboxaldehyde (FDC) is higher than those reported up to now. A further thermal exfoliation of the g-C3N4 samples showed under artificial light irradiation both an enhanced photocatalytic activity in conversion of HMF, and selectivity (ca. 42-45 %) towards FDC. The performance of the catalysts increased when the experiments were carried out under real outdoor illumination, reaching 50 % of selectivity versus FDC formation at 40 % of HMF conversion. The utilization of radical scavengers revealed that O2∙- was the main reactive species responsible for HMF oxidation to FDC. The photocatalytic test carried out under natural solar irradiation resulted in higher yields of FDC compared to that observed in the laboratory UV irradiated set-up, thus demonstrating the applicability of the exfoliated carbon nitride material in real-life conditions.

Graphitic carbon nitride assisted partial photocatalytic oxidation of the biomass platform molecule 5-hydroxymethyl-2-furfural (HMF) in aqueous medium was investigated. Different carbon nitride precursors were considered, being melamine the one yielding the most efficient photocatalyst The thermal exfoliation procedure of g-C3N4 gave rise to exfoliated samples with higher specific surface areas that also showed both an enhanced photocatalytic activity in conversion of HMF, and selectivity (ca. 42-45 %) towards FDC. The utilization of radical scavengers revealed that superoxide radicals were the main reactive species responsible for HMF oxidation to FDC. The use of natural solar light resulted in higher yields of FDC compared to that observed in the laboratory set-up, thus demonstrating the applicability of the exfoliated carbon nitride material in a real-life condition.

LaFeO3 perovskites both bare and containing 5 to 40 mol% of Cu(II) substituting Fe(III) have been prepared by the citrate auto-combustion synthesis method and used as heterogeneous photocatalysts for the degradation of 2-propanol in gas-solid regime under simulated solar light irradiation. The bare LaFeO3 resulted inactive, however the Cu(II) containing perovskite oxidized 2-propanol to propanone and eventually to CO2 and H2O. The most acive material resuted to be those with a 20% of Cu. Cu doping decreases the unit cell volume, and increases the distortion of (Fe/Cu)O6 octahedra, thus moving towards a configuration with four longer and two shorter bond lengths.

Photo)catalytic propylene hydration to 2-propanol and glycerol dehydration to acrolein reactions were carried out by using Keggin heteropolyacids (HPAs) supported on TiO2. Binary materials have been prepared by impregnation of H3PW12O40, H3PMo12O40 and H4SiW12O40, on TiO2 Evonik P25. Moreover, a binary material consisting of H4SiW12O40 and TiO2 was prepared via a hydrothermal treatment and tested for the same reactions. All the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy observations (SEM) coupled with energy dispersive X-rayand (EDX) measurements, diffuse reflectance spectroscopy (DRS), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). The supported Keggin HPA species played a key role both for the catalytic and for the photo-assisted catalytic reactions due to their strong acidity and ability to form strong oxidant species under UV irradiation.

In the present research commercial anatase (BDH) and anatase/rutile (P25) and home prepared anatase (HPA), rutile (HPR) and brookite (HPB) TiO2 polymorphs and have been used as supports for the deposition of metallic Pt. The Pt-TiO2 samples have been tested in the glucose conversion under anaerobic conditions. The presence of Pt resulted essential for the production of H2 and the home prepared samples resulted more active than the commercial ones.

In this work it is reported the conversion of glucose in aqueous dispersion of various TiO2 based photocatalysts. Aerobic and anaerobic conditions were used to study the distribution of the products both in the liquid (arabinose, gluconic acid, fructose and formic acid) and gas (H2 and CO2) phases. Commercial and home prepared bare and Pt-supported TiO2 samples were used as the photocatalysts.

In the last years a new category of TiO2 based composites prepared by impregnation of bare polycrystalline TiO2 powders with different sensitizers (i.e. phthalocyanines, porphyrins) permitted the improvement of the photocatalytic degradation of 4-nitrophenol (4-NP) under UV1-3 as well as under visible light irradiation.4 On the other hand growing interest devoted to the photodegradation of organic pollutants in water solutions by means of economically advantageous and environmental friendly processes are regarding this topic. Continuing our research in this area, we report here our recent results concerning: i) the preparation of new TiO2 and TiO2 based photocatalysts containing Fe and Cu species; ii) improvement of the photodegradation processes and conditions. 1. Mele, G.; Del Sole, R.; Vasapollo, G.; García-López, E.; Palmisano, L.; Schiavello, M. J. Catal. 2003, 217, 334. 2. Mele, G. ; Del Sole, R.; Vasapollo, G.; Marcì, G.; Garcìa-Lòpez, E.; Palmisano, L.; Coronado, J. M.; Hernández-Alonso, M. D.; Malitesta, C.; Guascito, R. J. Phys Chem. B 2005, 109, 12347. 3. Mele, G.; García-López, E.; Palmisano, L.; Dyrda, G.; Słota, R. J. Phys. Chem. C, 2007, 111, 6581. 4. Wang, C.; Li, J.; Mele, G.; Yang, G. M.; Zhang, F. X.; Palmisano, L.; Vasapollo, G. Appl. Catal. B: Environ. 2007, 76, 218.