Visible light driven photocatalytic decomposition of penicillin G by Ti 3+ self-doped TiO 2 nano-catalyst through response surface methodology

Abstract

Abstract In present study, Ti3+ self-doped TiO2 (r-TiO2) nano-catalyst was successfully fabricated by one-step solution reduction treatment in the presence of potassium borohydride. The self-doping process can induce the generation of Ti3+ and oxygen vacancy (Ov) to form a new energy level in the forbidden band of TiO2. Moreover, physicochemical properties of the resulting samples were studied by series of techniques. Results suggest that r-TiO2 nano-catalyst exhibits remarkable enhancement of visible light harvesting and higher charge separation efficiency. In order to investigate the influence factors on degradation of penicillin G (PENG), the experimental design was made using central composite method (CCD) of response surface methodology (RSM). For this purpose, the r-TiO2 dosage, PENG concentration and initial pH value were selected as critical parameters. Results indicate the r-TiO2 dosage and initial pH possess higher influences. Besides, the highest photocatalytic efficiency of PENG (98.3%) can be obtained under the optimal conditions of r-TiO2 dosage 50 mg, PENG concentration 100 mg/L and initial pH 5.5, respectively.