scholarly journals Development of Smart Composites Based on Doped-TiO2 Nanoparticles with Visible Light Anticancer Properties

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2589 ◽  
Author(s):  
Evdokia Galata ◽  
Eleni A. Georgakopoulou ◽  
Maria-Emmanouela Kassalia ◽  
Nefeli Papadopoulou-Fermeli ◽  
Evangelia A. Pavlatou
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Visible Light Irradiation ◽  
Sol Gel ◽  
Ultra Violet ◽  
Light Irradiation ◽  
Composite Particles ◽  
Doped Tio2 ◽  
X Ray ◽  
Anticancer Properties

In this study, the synthesis of smart, polymerically embedded titanium dioxide (TiO2) nanoparticles aimed to exhibit photo-induced anticancer properties under visible light irradiation is investigated. The TiO2 nanoparticles were prepared by utilizing the sol gel method with different dopants, including nitrogen (N-doped), iron (Fe-doped), and nitrogen and iron (Fe,N-doped). The dopants were embedded in an interpenetrating (IP) network microgel synthesized by stimuli responsive poly (N-Isopropylacrylamide-co-polyacrylicacid)–pNipam-co-PAA forming composite particles. All the types of produced particles were characterized by X-ray powder diffraction, micro-Raman, Fourier-transform infrared, X-ray photoelectron, ultra-violet-visible spectroscopy, Field Emission Scanning Electron, Transmission Electron microscopy, and Dynamic Light Scattering techniques. The experimental findings indicate that the doped TiO2 nanoparticles were successfully embedded in the microgel. The N-doped TiO2 nano-powders and composite particles exhibit the best photocatalytic degradation of the pollutant methylene blue under visible light irradiation. Similarly, the highly malignant MDA-MB-231 breast cancer epithelial cells were susceptible to the inhibition of cell proliferation at visible light, especially in the presence of N-doped powders and composites, compared to the non-metastatic MCF-7 cells, which were not affected.

scholarly journals Cu-Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity

2018 ◽  
Vol 8 (11) ◽  
pp. 2067 ◽  
Author(s):  
Snehamol Mathew ◽  
Priyanka Ganguly ◽  
Stephen Rhatigan ◽  
Vignesh Kumaravel ◽  
Ciara Byrne ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Density Functional ◽  
Anatase Phase ◽  
Sol Gel ◽  
Light Irradiation ◽  
Health Concern ◽  
Bacterial Inactivation ◽  
Doped Tio2 ◽  
X Ray

Surface contamination by microbes is a major public health concern. A damp environment is one of potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO2) can effectively curb this growing threat. Metal-doped titania in anatase phase has been proven as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu)-doped TiO2 (Cu-TiO2) was evaluated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO2 was carried out via sol-gel technique. Cu-TiO2 further calcined at various temperatures (in the range of 500–700 °C) to evaluate the thermal stability of TiO2 anatase phase. The physico-chemical properties of the samples were characterized through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV–visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO2 was maintained well, up to 650 °C, by the Cu dopant. UV–vis results suggested that the visible light absorption property of Cu-TiO2 was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasize the introduction of Cu+ and Cu2+ ions by replacing Ti4+ ions in the TiO2 lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9999%) was attained in 30 min of visible light irradiation by Cu-TiO2.

scholarly journals Photocatalytic Antibacterial Effectiveness of Cu-Doped TiO2 Thin Film Prepared via the Peroxo Sol-Gel Method

Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 352 ◽  
Author(s):  
Benjawan Moongraksathum ◽  
Jun-Ya Shang ◽  
Yu-Wen Chen
Keyword(s):  
Electron Microscopy ◽  
Methylene Blue ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Sol Gel ◽  
Light Irradiation ◽  
Gel Method ◽  
Doped Tio2 ◽  
X Ray ◽  
Photocatalytic Activities

Cu-doped titanium dioxide thin films (Cu/TiO2) were prepared on glass substrate via peroxo sol-gel method and dip-coating process with no subsequent calcination process for the degradation of organic dye and use as an antibacterial agent. The as-prepared materials were characterised using transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). For photocatalytic degradation of methylene blue in water, the samples were subjected to Ultraviolet C (UVC) and visible light irradiation. Degraded methylene blue concentration was measured using UV-Vis spectrophotometer. The antibacterial activities of the samples were tested against the gram-negative bacteria Escherichia coli (ATCC25922). Copper species were present in the form of CuO on the surface of modified TiO2 particles, which was confirmed using TEM and XPS. The optimal observed Cu/TiO2 weight ratio of 0.5 represents the highest photocatalytic activities under both UVC and visible light irradiation. Moreover, the same composition remarkably exhibited high antibacterial effectiveness against E. coli after illumination with ultraviolet A. The presence of CuO on TiO2 significantly enhanced photocatalytic activities. Therefore, active Cu-doped TiO2 can be used as a multipurpose coating material.

Preparation and Characterization of Nitrogen Doped TiO2 Nanoparticles as an Effective Catalyst in Photodegradation of Phenol under Visible Light

2014 ◽  
Vol 875-877 ◽  
pp. 28-33 ◽  
Author(s):  
Armineh Hassanvand ◽  
Morteza Sohrabi ◽  
Sayed Javid Royaee ◽  
Morteza Jafarikajour
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Surface Area ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Bet Surface Area ◽  
Doped Tio2 ◽  
X Ray ◽  
Nitrogen Doped ◽  
Degussa P25

Nitrogen-doped TiO2 nanoparticles of commercial Degussa P25 have been prepared via a direct impregnation reaction using ammonium hydroxide solution as nitrogen source. The Samples were characterized by X-ray diffraction (XRD), BET surface area BJH pore charecterization and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX). The results demonstrated that the nitrogen-doped TiO2 nanoparticles had a crystallite size 70.8 nm and a specific surface area of 6.4 m2/g with average pore diameter of 23.3 nm consisting mainly of titanium and oxygen. The photocatalyst activity was determined by degradation of phenol in an impinging stream reactor under visible light irradiation (λ> 400 nm). N-TiO2 catalyst exhibited higher photocatalytic activity in comparison with Degussa P25 under visible light irradiation.

Cu Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity and High Temperature Anatase Stability

2018 ◽  
Author(s):  
Snehamol Mathew ◽  
Priyanka Ganguly ◽  
Stephen Rhatigan ◽  
Vignesh Kumaravel ◽  
Ciara Byrne ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Density Functional ◽  
Anatase Phase ◽  
Sol Gel ◽  
Chemical Properties ◽  
Light Irradiation ◽  
Health Concern ◽  
Bacterial Inactivation ◽  
X Ray

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO<sub>2</sub>) can effectively curb this growing threat.<b> </b>Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO<sub>2 </sub>(Cu-TiO<sub>2</sub>) was evaluated against <i>Escherichia coli</i> (Gram-negative) and <i>Staphylococcus aureus</i> (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO<sub>2 </sub>was carried out <i>via</i> sol-gel technique. Cu-TiO<sub>2</sub> further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO<sub>2</sub> anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO<sub>2</sub> was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO<sub>2 </sub>was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu<sup>+</sup> and Cu<sup>2+</sup> ions by replacing Ti<sup>4+</sup> ions in the TiO<sub>2</sub> lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO<sub>2</sub>.

Hydrogen production from organic fatty acids using carbon-doped TiO2 nanoparticles under visible light irradiation

2018 ◽  
Vol 43 (9) ◽  
pp. 4335-4346 ◽  
Author(s):  
Yang Li ◽  
Liyuan Kuang ◽  
Dequan Xiao ◽  
Appala Raju Badireddy ◽  
Maocong Hu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Hydrogen Production ◽  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Doped Tio2 ◽  
Carbon Doped

scholarly journals Enhanced Photocatalytic Properties of PET Filaments Coated with Ag-N Co-Doped TiO2 Nanoparticles Sensitized with Disperse Blue Dyes

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 987 ◽  
Author(s):  
Hui Zhang ◽  
Qi Tang ◽  
Qingshan Li ◽  
Qingwen Song ◽  
Hailiang Wu ◽  
...  
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Visible Light Irradiation ◽  
Reaction Rate Constant ◽  
Light Irradiation ◽  
Photocatalytic Properties ◽  
Blue Dye ◽  
Dye Sensitization ◽  
Doped Tio2 ◽  
Co Doped

In this study, the effects of disperse blue dye-sensitization on the photocatalytic properties of the Ag-N co-doped TiO2 nanoparticles loaded on polyethylene terephthalate (PET) filaments are investigated under visible light irradiation. The microstructure and photocatalytic properties of the as-synthesized TiO2 nanocomposites, as well as the as-prepared PET filaments, are systematically characterized. The photocatalytic performance of the PET filaments coated with the Ag-N co-doped TiO2 nanoparticles sensitized with disperse blue dyes is evaluated via its capacity of photo-degrading methyl orange (MO) dyes under visible light irradiation. It is found that the holes are the predominant reactive radical species and the hydroxyl and superoxide radicals play a subordinate role in the photocatalytic reaction process. The reaction rate constant of the photocatalytic composite filaments is nearly 4.0 times higher than that of the PET filaments loaded solely with TiO2 nanoparticles. The resultant photocatalytic composite filaments are evident to be capable of repeatedly photo-degrading MO dyes without losing its photocatalytic activity significantly.

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