Sunlight assisted photocatalytic mineralization of organic pollutants over rGO impregnated TiO2 nanocomposite: Theoretical and experimental study
Abstract
In this work, the spectrum and electrochemical characterization of prepared rGO incorporated TiO2 photocatalyst was carried out and it activity was investigated under direct sunlight for the degradation of Congo Red (CR) and tricloroacetic acid pollutant. The chemical structural, morphology and spectral properties of catalysts were characterized utilizing X-ray diffraction, Raman spectroscopy, X-photoelectron microscopy, transmission electron microscopy (TEM), and photoluminescence spectroscopy (PL) respectively. The TiO2 catalyst with different loading rGO from 1% to 10%, showed higher photoactivity as compared to pure TiO2. Efforts were made to connect the improvement activity of rGO loaded TiO2 with spectrum and electrochemical properties. At lower incorporating (1%rGO), the improvement photodegradation was assign to the excited trap of electrons, while the electron trap and synergic effect between rGO and TiO2 played the main role in higher loading. The electrochemical properties of rGO loading TiO2 were characterized by electrochemical impedance spectroscopy (EIS). The determination of intermediates and investigation of the released anions appeared the supporting of superoxide and hydroxyl radicals in degradation process. This study showed that 2,4-dichorophenoxy acetic acid degrades at a higher rate than congo red. The photodegradation mechanism of dyes under sunlight was studied by LC-Mass and the scavenger effect. Under sunlight, the photodegradation of congo red and tricloroacetic acid using pure and rGO incorporated TiO2 was adjusted at normal conditions with excellent efficiency.