Fabrication of Titanium Dioxide/Carbon Fiber (TiO2/CF) Composites for Removal of Methylene Blue (MB) from Aqueous Solution with Enhanced Photocatalytic Activity

Abstract

TiO2 powder was firstly synthesized and carbon fiber was secondly prepared via the carbonization of polyaniline fiber, and TiO2/carbon fiber composites were lastly synthesized via a simple method at room temperature. The prepared samples are evidently investigated by X-ray powder diffraction, scanning electron microscopy, energy dispersive spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, photoluminescence spectrum, and X-ray photoelectron spectroscopy, respectively. Using the monochromatic light of ultraviolet, the photocatalytic activity of the TiO2/CF composites was accurately evaluated with respect to the degradation of an aqueous dye (methylene blue) solution. The relationship between the photocatalytic degradation of methylene blue dye and its ratio, contact time, and the amount of catalyst was studied. The kinetics and mechanisms of degradation were discussed. The results show that TiO2/CF composites have good photocatalytic activity and stability. The TiO2/CF2/1 composite was used in effective photocatalytic degradation of methylene blue, the weight ratio of TiO2 to carbon fiber was 2:1, and the degradation rate was obtaining up to 97.7% of degradation during 120 min of reaction. The photocatalytic stability of TiO2/CF composites was dependent on the stability of their structure. After 5 repeated uses, the composite TiO2/CF2/1 still exhibited rather high activity toward the degradation of methylene blue, where the decolorization efficiency of methylene blue achieved 92% and the loss of activity was negligible. Based on radical trapping experiments, the mechanism of TiO2/CF composites on photocatalytic degradation of methylene blue is proposed, which could explain the enhanced photocatalytic activity of the composites better. Superoxide radicals, photogenerated holes, and photogenerated electrons were the main active substances for methylene blue degradation.

Recycling Carbon Fiber-Reinforced Polymers (CFRPs) to Construct CFs/TiO2 Nanotexture with Efficient Interface Charge Transfer for Stimulating Photocatalytic Hydrogen Production

“…Figure e shows PL analysis of CF, TiO 2 -A, TiO 2 -S, CF/TiO 2 -A, and CF/TiO 2 -S composite samples. In the case of pure CF, the lowest PL intensity was obtained, which was probably due to conductive characteristics and because of the blackish color, and similar observations were reported previously . Using pristine TiO 2 -S, the highest PL intensity was observed, whereas TiO 2 -A showed lower PL intensity.…”

“…This amount of H 2 production was 2.87 fold higher than using pristine TiO 2 -A. Due to the CFs’ conductive properties, which effectively separate photoinduced electrons and holes over the TiO 2 surface, there was a notable increase in hydrogen productivity . However, any loading of CF above 3 wt % has adverse effect on the hydrogen evolution, whereas the lowest H 2 yield was obtained with 5 wt % CF loading with TiO 2 -A.…”

“…The results indicate that the presence of CFs in TiO 2 could further enhance the light absorption efficiency, which is expected to improve the photocatalytic activity of the composite. In the past, it was reported and observed that CF/TiO 2 composites clearly enhanced absorption in the visible light band …”

Nanocrystalline Titanium Dioxide Dipped with AlCl2 as a Humidity Sensors

“…All the peaks are perfectly match with Periclase TiO2 nanostructure, which indicates that Periclase TiO2 nanoparticles obtained. No other peaks were detected in spectrum within detection limit of XRD instrument, indicating the pure periclase TiO2 Nanomaterial is synthesized [19][20][21][22][23][24][25].…”

Recent Advances in the Removal of Organic Dyes from Aqueous Media with Conducting Polymers, Polyaniline and Polypyrrole, and Their Composites

“…The morphology is retained after this process, except for some shrinkage. Carbon fibers prepared from the polyaniline precursor were combined with titanium dioxide to produce a photocatalyst for the decomposition of methylene blue [ 148 ].…”