Effect of calcination temperature on the photocatalytic activity of carbon-doped titanium dioxide revealed by photoluminescence study

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Nor Arbani Sean, Wai Loon Leaw, Hadi Nur

2019 Journal of the Chinese Chemical Society Vol. 66 Issue 10 Article Cited by 16 Quartile

Abstract

Carbon-doped titania (C-TiO2) nanoparticles were synthesized by the sol–gel method at different calcination temperatures (300–600°C) employing titanium tetraisopropoxide (TTIP) as the titanium source and polyoxyethylene sorbitan monooleate (Tween 80) as the carbon source. The physical properties of C-TiO2 samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic activities were checked through the photodegradation of phenolphthalein (PHP) under ultraviolet irradiation. The UV spectrum showed that the carbon doping extends the absorption range of TiO2 to the visible region. However, the photocatalytic activity is affected by the electron–hole recombination phenomenon, as revealed by the photoluminescence (PL) study. According to the PL spectra, carbon doping reduces the edge-to-edge electron–hole recombination. Nevertheless, the number of defect sites is greatly influenced by the calcination temperature of C-TiO2. C-TiO2 that was calcined at 400°C showed the highest photodegradation percentage of PHP, which was mainly attributed to the synergic effect of the low direct edge-to-edge electron–hole recombination, high content of defect sites, and retention of active electrons on the surface hydroxyl group. © 2019 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Affiliations

Centre for Sustainable Nanomaterials, Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, UTM Skudai, Johor, Malaysia; Central Laboratory of Minerals and Advanced Materials, Faculty of Mathematics and Natural Science, State University of Malang, Malang, Indonesia