Photoelectrochemical characteristics, photodegradation and kinetics of metal and non-metal elements co-doped photocatalyst for pollution removal

Abstract

Considering coordination effects, this study prepared a photocatalyst with a highly visible light respondence using co-doped titania with non-metal (nitrogen and sulfur) and lanthanide metal ions (cerium). As well, the photoelectrochemical characteristics and photocatalytic effects were tested. The feasibility was investigated on the power of the photoelectrochemical solar cell and the photodegradation of volatile organic compounds (VOCs) from indoor air pollution, taking toluene as a model compound. In this study, the different intensities of a light-emitting diode (LED) and the different initial concentrations (10–50ppmv) were examined, and the kinetic model was addressed. The maximum power (Pm) at white light emitting diode (WLED) was 35.5 and 174.68times that of the solar cell without cerium doping and without Ce, N and S doping, respectively. The decomposition efficiency (ηD) was more than 99.9% below 30ppmv at 5050WLED with 10Ce/TiNxSyO2−x−y (10Ce/TNST). The photocatalytic decomposition was elucidated according to the Langmuir-Hinshelwood model. The reaction rate constant (k) and adsorption equilibrium constant (KL) of 10Ce/TNST with 5050WLED in the range of 10–50ppmv were 0.2637ppmvmin−1 and 0.7008ppmv−1, respectively. This study succeeded in predicting optimum photodegradation conditions from the PECSC test. The photocurrent and power from the co-doped photocatalysts are related to the photodegradation efficiency.