Abstract

We present a facile and green approach to produce crystalline TiO₂ nanoparticles on a surface of different carbonaceous materials derived from lignocellulosic biomass such as STARBON-800® obtained by carbonization at 800 ^oC and biochar-SWP700 (Soft Wood Pellets (SWP) obtained by pyrolysis at 700 ^oC) via novel low temperature ultrasound-promoted green methodology coupled with citric acid as a cross-linking agent. In comparison to other methods, the developed method has several significant benefits such as simplicity, great ability to get crystalline TiO₂ particles (elimination of high-temperature treatment (material calcination at > 300 ^oC) needed in the conventional sol-gel method, which is extremely important in transforming amorphous TiO₂ into a photoactive crystalline phase) elimination of risky chemicals and oxidizing agent, and also ability to change some parameters (e.g. ultrasound intensity). Prepared materials were characterized by XRD, DR UV– vis, N₂ physisorption, HR-XPS, XRF, HR-TEM, FT-IR and subsequently tested for their photocatalytic activities both in photocatalytic phenol degradation (in water) and oxidation of methanol (in air) under UV and visible light irradiation.