1. PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black
- Author
-
Sarre K. M. Nzaba, Bhekie B. Mamba, Bulelwa Ntsendwana, and Alex T. Kuvarega
- Subjects
Materials science ,Infrared ,Health, Toxicology and Mutagenesis ,02 engineering and technology ,General Medicine ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Pollution ,0104 chemical sciences ,symbols.namesake ,Ultraviolet visible spectroscopy ,symbols ,Photocatalysis ,Environmental Chemistry ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Spectroscopy ,Raman spectroscopy ,Photodegradation ,Visible spectrum - Abstract
This study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal co-doped TiO2. N,Pt co-doped TiO2 photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PG0) as a template and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet/visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25, revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N,Pt co-doped TiO2 was measured by the reaction of photocatalytic degradation of BB dye. Enhanced photodegradation efficiency of BB was achieved after 180-min reaction time with an initial concentration of 50 ppm. This was attributed to the rod-like shape of the materials, larger surface area, and enhanced absorption of visible light induced by N,Pt co-doping. The N,Pt co-doped TiO2 also exhibited pseudo-first-order kinetic behavior with half-life and rate constant of 0.37 and 0.01984 min-1, respectively. The mechanism of the photodegradation of BB under the visible light irradiation was proposed. The obtained results prove that co-doping of TiO2 with N and Pt contributed to the enhanced photocatalytic performances of TiO2 for visible light-induced photodegradation of organic contaminants for environmental remediation. Therefore, this work provides a new approach to the synthesis of PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black.
- Published
- 2018
- Full Text
- View/download PDF