Study on light emission diode/carbon modified TiO2 system for tetracycline hydrochloride degradation

In this study, the photocatalytic performance of carbon modified TiO2 (MCT)) synthesized via a facile microwave method was evaluated by degrading tetracycline hydrochloride (TH) under Red-Green-Blue - Light Emission Diode (RGB-LED) light. The materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), N-2 sorption isotherm, photoluminescence (PL), Fourier transform infrared (FT-IR), and UV-diffused reflectance spectroscopy (UV-DRS). Parameters employed for optimizing the photocatalytic degradation system were catalyst concentration, pH, light intensity (levels) and RGB-LED colour. The BET surface area, BJH desorption pore volume and diameter of MCT was slightly higher than the pure TiO2. Although both the pure TiO2 and MCT have about the same band gap energy (approximate to 3.14 eV), MCT extended into the visible region. Results of the PL experiment showed that MCT had a lower electron-hole recombination rate which invariably improved its photocatalytic performance. Results from the photocatalytic degradation experiments showed that the reactions followed the pseudo first order kinetics. TH had an optimum degradation (74%, K-app = 1.22 x 10(-2) min(-1)) at pH 7, catalyst concentration of 300 mg/L, and White-LED light intensity of 46 W/m(2) after 2 h of irradiation.