Glucosamine-induced growth of highly distributed TiO2 nanoparticles on graphene nanosheets as high-performance photocatalysts

The evolution of desirable physico-chemical properties in high performance photocatalyst materials involves steps that must be carefully designed, controlled, and optimized. This study investigated the role of key parameter in the preparation and photocatalytic activity analysis of the mixed phase of anatase/rutile TiO2 nanoparticles, prepared via sol-gel method containing titanium-n-butoxide Ti(OBu)4 as a precursor material, nitric acid as catalyst, and isopropanol as solvent. The prepared TiO2 nanoparticles were characterized by means of XRD, SEM, and BET analyses, and UV-Vis-NIR spectroscopy. The results indicated that the calcination temperature play an important role in the physico-chemical properties and photocatalytic activity of the resulting TiO2 nanoparticles. Different calcination temperatures would result in different composition of anatase and rutile. The photocatalytic activity of the prepared mixed phase of anatase/rutile TiO2 nanoparticles was measured by photodegradation of 50 ppm phenol in an aqueous solution. The commercial anatase from Sigma-Aldrich and Degussa P25 were used for comparison purpose. The mixed phase of anatase/rutile TiO2 nanoparticles (consists of 38.3% anatase and 61.7% rutile) that was prepared at 400°C exhibited the highest photocatalytic activity of 84.88% degradation of phenol. The result was comparable with photocatalytic activity demonstrated by Degussa P25 by 1.54% difference in phenol degradation. The results also suggested that the mixed phase of anatase/rutile TiO2 nanoparticles is a promising candidate for the phenol degradation process. The high performance of photocatalyst materials may be obtained by adopting a judicious combination of anatase/rutile and optimized calcination conditions.

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Enhanced Photocatalytic Activity of Au/TiO2 Nanoparticles against Ciprofloxacin

Catalysts ◽

10.3390/catal10020234 ◽

2020 ◽

Vol 10 (2) ◽

pp. 234 ◽

Cited By ~ 1

Author(s):

Pedro Martins ◽

Sandro Kappert ◽

Hoai Nga Le ◽

Victor Sebastian ◽

Klaus Kühn ◽

...

Keyword(s):

Photocatalytic Activity ◽

Computational Modeling ◽

Tio2 Nanoparticles ◽

High Performance ◽

Experimental Tests ◽

Precipitation Method ◽

Visible Range ◽

Visible Radiation ◽

Major Drawback ◽

Tio2 Anatase

In the last decades, photocatalysis has arisen as a solution to degrade emerging pollutants such as antibiotics. However, the reduced photoactivation of TiO2 under visible radiation constitutes a major drawback because 95% of sunlight radiation is not being used in this process. Thus, it is critical to modify TiO2 nanoparticles to improve the ability to absorb visible radiation from sunlight. This work reports on the synthesis of TiO2 nanoparticles decorated with gold (Au) nanoparticles by deposition-precipitation method for enhanced photocatalytic activity. The produced nanocomposites absorb 40% to 55% more radiation in the visible range than pristine TiO2, the best results being obtained for the synthesis performed at 25 °C and with Au loading of 0.05 to 0.1 wt. %. Experimental tests yielded a higher photocatalytic degradation of 91% and 49% of ciprofloxacin (5 mg/L) under UV and visible radiation, correspondingly. Computational modeling supports the experimental results, showing the ability of Au to bind TiO2 anatase surfaces, the relevant role of Au transferring electrons, and the high affinity of ciprofloxacin to both Au and TiO2 surfaces. Hence, the present work represents a reliable approach to produce efficient photocatalytic materials and an overall contribution in the development of high-performance Au/TiO2 photocatalytic nanostructures through the optimization of the synthesis parameters, photocatalytic conditions, and computational modeling.

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Solution-based synthesis of graphene nanosheets and functional TiO2 nanoparticles in high-performance dye-sensitized solar cells

10.5353/th_b5610932 ◽

2015 ◽

Author(s):

Peng Zhai

Keyword(s):

Solar Cells ◽

Tio2 Nanoparticles ◽

High Performance ◽

Graphene Nanosheets ◽

Dye Sensitized Solar Cells ◽

Dye Sensitized ◽

Sensitized Solar Cells

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Photocatalytic activity of Fe and Cu co-doped TiO2 nanoparticles under visible light

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-021-05556-4 ◽

2021 ◽

Author(s):

Charitha Thambiliyagodage ◽

Shanitha Mirihana

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Tio2 Nanoparticles ◽

Doped Tio2 ◽

Co Doped

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A Facile Urea-Assisted Thermal Decomposition Process of TiO2 Nanoparticles and Their Photocatalytic Activity

Coatings ◽

10.3390/coatings11020165 ◽

2021 ◽

Vol 11 (2) ◽

pp. 165

Author(s):

Sandip Madhukar Deshmukh ◽

Mohaseen S. Tamboli ◽

Hamid Shaikh ◽

Santosh B. Babar ◽

Dipak P. Hiwarale ◽

...

Keyword(s):

Thermal Decomposition ◽

Photocatalytic Activity ◽

Tio2 Nanoparticles ◽

Large Scale ◽

Ultra Violet ◽

Tio2 Nps ◽

Transmission Electron ◽

Structures And Properties ◽

Ft Ir ◽

Large Scale Synthesis

In the present work, we have reported a facile and large-scale synthesis of TiO2 nanoparticles (NPs) through urea-assisted thermal decomposition of titanium oxysulphate. We have successfully synthesized TiO2 NPs by using this effective route with different weight ratios of titanium oxysulphate: urea. The structures and properties of TiO2 NPs were confirmed by scanning electron microscope) (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FT-IR), ultra violet–visible spectroscopy (UV-vis), and photoluminescence (Pl) techniques. XRD demonstrated that TiO2 NPs holds of anatase crystal phase with crystallizing size 14–19 nm even after heating at 600 °C. TGA, SEM, and TEM images reveal urea’s role, which controls the size, morphology, and aggregation of TiO2 NPs during the thermal decomposition. These TiO2 NPs were employed for photodegradation of Methyl Orange (MO) in the presence of ultraviolet (UV) radiation. An interesting find was that the TiO2 NPs exhibited better photocatalytic activity and excellent recycling stability over several photodegradation cycles. Furthermore, the present method has a great perspective to be used as an efficient method for large-scale synthesis of TiO2 NPs.

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Constructing MoO2@MoS2 Heterostructures Anchored on Graphene Nanosheets as a High-Performance Anode for Sodium Ion Batteries

Electrochimica Acta ◽

10.1016/j.electacta.2021.138612 ◽

2021 ◽

pp. 138612

Author(s):

Yuxiang Luo ◽

Xiaobo Ding ◽

Xiangdong Ma ◽

Dongdong Liu ◽

Haikuo Fu ◽

...

Keyword(s):

High Performance ◽

Graphene Nanosheets ◽

Sodium Ion ◽

Sodium Ion Batteries

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SnS2/TiO2 Nanocomposites for Hydrogen Production and Photodegradation Under Extended Solar Irradiation

Catalysts ◽

10.3390/catal11050589 ◽

2021 ◽

Vol 11 (5) ◽

pp. 589

Author(s):

Sivagowri Shanmugaratnam ◽

Balaranjan Selvaratnam ◽

Aravind Baride ◽

Ranjit Koodali ◽

Punniamoorthy Ravirajan ◽

...

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Hydrogen Evolution ◽

Environmental Remediation ◽

High Performance ◽

Degradation Mechanism ◽

Solar Irradiation ◽

Earth Abundant ◽

Improved Performance ◽

Chalcogenide Materials

Earth–abundant transition metal chalcogenide materials are of great research interest for energy production and environmental remediation, as they exhibit better photocatalytic activity due to their suitable electronic and optical properties. This study focuses on the photocatalytic activity of flower-like SnS2 nanoparticles (composed of nanosheet subunits) embedded in TiO2 synthesized by a facile hydrothermal method. The materials were characterized using different techniques, and their photocatalytic activity was assessed for hydrogen evolution reaction and the degradation of methylene blue. Among the catalysts studied, 10 wt. % of SnS2 loaded TiO2 nanocomposite shows an optimum hydrogen evolution rate of 195.55 µmolg−1, whereas 15 wt. % loading of SnS2 on TiO2 exhibits better performance against the degradation of methylene blue (MB) with the rate constant of 4.415 × 10−4 s−1 under solar simulated irradiation. The improved performance of these materials can be attributed to the effective photo-induced charge transfer and reduced recombination, which make these nanocomposite materials promising candidates for the development of high-performance next-generation photocatalyst materials. Further, scavenging experiments were carried out to confirm the reactive oxygen species (ROS) involved in the photocatalytic degradation. It can be observed that there was a 78% reduction in the rate of degradation when IPA was used as the scavenger, whereas around 95% reduction was attained while N2 was used as the scavenger. Notably, very low degradation (<5%) was attained when the dye alone was directly under solar irradiation. These results further validate that the •OH radical and the superoxide radicals can be acknowledged for the degradation mechanism of MB, and the enhancement of degradation efficiency may be due to the combined effect of in situ dye sensitization during the catalysis and the impregnation of low bandgap materials on TiO2.

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