Enhanced solar light photodegradation of brilliant black bis-azo dye in aqueous solution by F, Sm3+ codoped TiO2

3rd International Conference on Structural Nano Composites

材料科学;化学

Mukonza, Sabastian S.^1 ; Nxumalo, Edward N.^1 ; Mamba, Bhekie B.^1 ; Mishra, Ajay K.^1

Nanotechnology and Water Sustainability (NanoWS) Research Unit, College of Science Engineering and Technology (CSET), University of South Africa (UNISA), Florida, Johannesburg

1705, South Africa^1

关键词: Degradation efficiency;    Energy dispersive X ray spectroscopy;    Photocatalytic efficiency;    Photocatalytic performance;    Pseudo first-order kinetics;    Trivalent samarium ion;    Visible-light activity;    X-ray diffraction spectroscopy;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/195/1/012006/pdf
DOI  :  10.1088/1757-899X/195/1/012006

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

This research focuses on improving the photocatalytic efficiency of TiO2during the photo-mineralisation of brilliant black (BN) bis-azo dye pollutant in aqueous solution. This was achieved by improving the visible light activity of TiO2photocatalyst semiconductor through co-doping of fluorine (F) and trivalent samarium ions (Sm3+) into a TiO2matrix using a modified sol-gel synthesis method. Structural, morphological, and textural properties were evaluated using ultra-violet /visible spectroscopy (UV-visible), Raman spectroscopy, scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction spectroscopy (XRD). Photocatalytic and degradation efficiencies were assessed by decolourisation of BN dye in aqueous solution. Complete degradation of BN was attained after an irradiation time of 3 h using F, Sm3+-TiO2(0.6% Sm3+) compared to 73.4% achieved using pristine TiO2. Pseudo first order kinetics rate constants (Ka) were 2.73×10-2and 6.6×10-3min-1for Sm3+-TiO2(0.6%Sm3+) and pristine TiO2, respectively, which translates to a remarkably high enhancement factor of 4. The results obtained established that doping of TiO2by F and Sm3+enhances the photocatalytic performance of TiO2during solar light radiation which enables the utilisation of freely available and clean solar energy.