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

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.

Behaviour of Titanium Dioxide Particles in Artificial Body Fluids and Human Blood Plasma

“…The particles are spherical with an irregular shape and a rough surface ( Figure 1 C,D). The morphology corresponds to the study of [ 30 ].…”

Laser Desorption/Ionization Mass Spectrometry as a Potential Tool for Evaluation of Hydroxylation Degree of Various Types of Titanium Dioxide Materials

“…One of the most important features of the TiO 2 surface is the number and distribution of the hydroxyl groups present on it [5][6][7][8][9]. For example, it has been demonstrated and discussed in detail, that the surface hydroxylation degree is of crucial importance for selective adsorption of Cr(VI) [10], photocatalytic oxidation/degradation of methyl ethyl ketone [11], phenolphthalein [12], methyl orange, rhodamine B, p-chlorophenol [13], methylene blue [14], adsorption of CO 2 , SO 2 , NO 2 [15]. The most common method for the study of surface hydroxylation degree, or more precisely the tool which enables comparison of the TiO 2 hydroxylation degrees, is the Fourier-transform infrared spectroscopy (FTIR) [8][9][10][11][12][13][14][15], which sometimes is supported by X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption or surface acid-base ion-exchange reactions method [7,10,13].…”

Visible light‐excited surface plasmon resonance charge transfer significantly improves the photocatalytic activities of ZnO semiconductor for pollutants degradation

“…[ 16–26 ] Different photocatalysts applied to treat pollutants effectively include TiO 2 , ZnO, and SnO 2. [ 27–32 ] Among these photocatalysts, ZnO has shown enhanced stability under extreme condition of temperature and redox environment. [ 33 ] However, these photocatalysts absorb only UV light owing to their large band gaps.…”