The preparation, properties and heterogeneous photocatalytic applications of TiO2 immobilized on carbon materials derived from earth-abundant, renewable and biodegradable agricultural residues and sea food waste resources are reviewed.

A series of new inorganic-organic hybrid materials based on TiO2 and new biochar-based supports (biochar obtained by pyrolysis of Miscanthus Straw Pellets (MSP) and Soft Wood Pellets (SWP) at 550 and 700 o C) were successfully prepared using ultrasound-assisted methodology. The resulting composites were characterized by a wide range physicochemical techniques and investigated in water and gas phase photocatalytic test reaction. Our best composite (TiO2/SWP700) achieved phenol degradation of 64.1% (under UV light) and 33.6% (under visible light). In addition, it also showed an extraordinarily high activity (~90 %) in selective oxidation of methanol to methyl formate in flow gas phase, high selectivity to methyl formate (~80 %) and high yield of methyl formate (~88 %) after 240 minutes of illumination. It can be noticed that when TiO2 is supported on biochar, presented a superior photocatalytic ability and could be recycled at least 5 times in both photocatalytic runs tests with reproducible high photocatalytic efficiency.

The aim of this work is to develop bimetallic Pd-Au/TiO2 P90 systems, which are highly active and selective for the photocatalytic oxidation of methanol to form methyl formate. Modification of commercial TiO2 P90 with Pd-Au nanoparticles was successfully achieved for the first time by means of a sonophotodeposition (SPD) method. The prepared materials were characterized by TEM, UV/Vis spectroscopy, X-ray photoelectron spectroscopy, and powder XRD. The Pd-Au bimetallic nanoparticles supported on titania exhibited remarkably enhanced catalytic activity in selective methanol oxidation to form methyl formate due to the synergism of Au and Pd particles, as well as the strong interaction between TiO2 and Pd-Au. SPD is a green methodology that can be used to prepare well-defined bimetallic surfaces on semiconductor supports with great promise for catalytic applications, in which selectivity can be tuned through adjustment of the surface composition.

Novel carbonaceous support (Starbon) for TiO2 photocatalysts synthesized by a simple ultrasound-assisted impregnation technique. High phenol photo-oxidation rate to complete mineralization. Renewable materials for a straightforward photocatalysts synthesis.