Structural Characterization and Photocatalytic Activity of Synthesized Carbon Modified TiO₂ for Phenol Degradation

Abstract

To promote the photocatalytic performance TiO₂ and enlarge its application in visible region, carbon doped TiO₂ (C/TiO₂) composites were synthesized by wet impregnation method using sucrose as a precursor and used for phenol photocatalytic reaction. The synthesized products were characterized by Nitrogen adsorption-desorption isotherms (BET), X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-visible diffuse reflectance spectroscopy (UV-vis) techniques. The results showed that the obtained TiO₂ was anatase phase in the C/TiO₂ products, and its crystallite size was 11.7 nm, respectively. Carbon amount and calcined temperature of C/TiO₂ can promote phenol removal. In this experiment, 5% carbon and 500 °C are the best choice for photocatalyst preparation. Under the UV light irradiation, 5%C/TiO₂ (500 °C, 2 h) exhibited the efficiency of 70.0% for phenol degradation within 150 min whereas TiO₂ (500 °C, 2 h) had 53.0% in the same duration of time. Also 5%C/TiO₂ (500 °C, 2 h) has higher photocatalytic performance under sunlight than pure TiO₂. A combination of factors that include the smallest crystalline size, higher anatase percent, less band gap energy value and more oxygen vacant resulted in higher photocatalytic activities of 5%C/TiO₂ (500 °C, 2 h).

Keywords

C/TiO₂ / photocatalytic / phenol degradation

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