Synthesis, characterization, and photocatalytic properties of reed biochar/TiO2 composites

In this study, TiO2/biochar (TBC) materials were successfully synthesized by simple hydrolysis. The photocatalytic activity of the products was evaluated through the photodegradation ability of doxycycline (DC) in aqueous solution. Characterization shows that TiO2 nanoparticles are well dispersed on the biochar surface. The presence of biochar helped improve the specific surface area, narrow the band gap and enhance the optical absorption in the visible light region of TiO2. The TBC composite at TiO2/biochar mass ratio = 1/0.25 showed the highest photodegradation efficiency, about 3.77 times higher than pure TiO2. Kinetic studies showed that DC degradation followed an apparent first-order kinetic model with rate constant kapp = 2.66×10-2 min-1 at DC concentration of 7.0 mg/L. Research shows that TiO2/biochar material has great potential for treating antibiotic-contaminated wastewater.