Nano Gold Doped Nano TiO2 – An Efficient Solar Photocatalyst for the Degradation of Persistent Organic Pollutants

Novel nanogold doped TiO2nanoparticles are found to be highly efficient for the photocatalytic degradation of organic pollutants. TiO2nanoparticles were synthesized from titanium (IV) isopropoxide through hydrothermal route. Gold nanoparticles were prepared by chemical reduction and stabilization employing D-glucosamine, and were doped in TiO2nanoparticles. The analysis revealed that the diameter of gold nanoparticles used for doping is around 5 nm. Undoped and gold doped samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, UV-Vis diffuse reflectance spectra (DRS) and field emission scanning electron microscopy (SEM). DRS study showed that nanogold doping in titania nanoparticles induces a shift of absorption edge to the visible range and reduces the band gap. Complementing our earlier finding that noble metal doping in titania nanoparticles enable photocatalytic activity in the visible region, it is showed that gold doping enhances photocatalytic activity of the titania nanoparticles. This was confirmed by the degradation of the dye methylene blue repeatedly using gold doped nanoparticles under direct sunlight. Further, the nanoparticles were used to study the degradation of the persistent organic pollutant, β endosulfan, and near complete degradation were observed in an hour. Regenerated nanoparticles were found effective for the degradation of the pesticide for more than three cycles.

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Hierarchical Z-scheme 1D/2D architecture with TiO2 nanowires decorated by MnO2 nanosheets for efficient adsorption and full spectrum photocatalytic degradation of organic pollutants

Catalysis Science & Technology ◽

10.1039/d0cy00419g ◽

2020 ◽

Vol 10 (11) ◽

pp. 3603-3612

Author(s):

Jiejing Zhang ◽

Yajie Hu ◽

Hong Zheng ◽

Pengyi Zhang

Keyword(s):

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Organic Pollutants ◽

Organic Pollutant ◽

Pollutant Removal ◽

Tio2 Nanowires ◽

Full Spectrum ◽

Mno2 Nanosheets ◽

Excellent Stability

A novel hierarchical 1D/2D TiO2/MnO2 composite shows superior adsorption, full spectrum photocatalytic activity and excellent stability for organic pollutant removal.

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Synthesis of Cu2(OH)PO4 superstructures with NIR-laser enhanced photocatalytic activity

Functional Materials Letters ◽

10.1142/s1793604720500150 ◽

2020 ◽

Vol 13 (03) ◽

pp. 2050015 ◽

Cited By ~ 1

Author(s):

Lu Cheng ◽

Nuo Yu ◽

Yan Zhang ◽

Zhun Shi ◽

Haifeng Wang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Near Infrared ◽

Visible Region ◽

Photogenerated Electron ◽

Photothermal Effect ◽

Hydrothermal Route ◽

Electron Hole ◽

Light Group ◽

Nir Laser

The development of photocatalysts with wide UV-Vis-near-infrared (NIR) photoabsorption has received tremendous interest for utilizing sunlight efficiently. In this work, Cu2(OH)PO4 superstructures are prepared by a simple hydrothermal route, and they have strong bandgap absorption in UV-Visible region and a distinctive plasmon resonance absorption in NIR region. Under the synergetic illumination of visible light and 980[Formula: see text]nm laser (3.0[Formula: see text]W[Formula: see text]cm[Formula: see text]), Cu2(OH)PO4 superstructures can degrade 89.2% MB with the elevated temperature ([Formula: see text]51∘C) of solution, which is higher than that from visible light group (50.0%), laser group (16.4%), and visible-light/exterior-heating group (62.5%, same temperature at [Formula: see text]51.0∘C). These facts reveal that Cu2(OH)PO4 superstructures exhibit NIR-laser enhanced photocatalytic activity, which not only comes from the photothermal effect-induced temperature elevation, but also mainly results from the increased production of photogenerated electron-hole pairs by NIR-laser. Therefore, Cu2(OH)PO4 superstructures can act as efficient photocatalyst with NIR-laser enhanced photocatalytic activity.

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Preparation of Silver-Doped TiO2 Photoatalyst via a Simple Sol-Hydrothermal and their Visible Light Photocatalytic Activity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.694.824 ◽

2011 ◽

Vol 694 ◽

pp. 824-830 ◽

Cited By ~ 2

Author(s):

Li Guo ◽

Feng Fu ◽

Dan Jun Wang ◽

Xiao Dan Qiang ◽

Qing Bo Wei ◽

...

Keyword(s):

Photocatalytic Activity ◽

Anatase Phase ◽

Visible Region ◽

Tio2 Photocatalyst ◽

Hydrothermal Route ◽

Nano Tio2 ◽

Absorption Intensity ◽

Ag Doping ◽

Vis Spectroscopy ◽

Visible Light Photocatalytic

Silver-doped nano-TiO2 photocatalyst were synthesized via a simple hydrothermal route. The samples were characterized by XRD, XPS, FE-SEM and UV-Vis absorption spectrum techniques. Rhodamine B was selected as the model-pollutant to evaluate the photocatalytic activity of the samples. The XRD results indicated that the Ag-doped TiO2 were pure anatase phase. The UV-Vis spectroscopy revealed that the Ag doping can increase the absorption intensity of TiO2 in the visible region, which results in the improving the photocatalytic activity of TiO2 photocatalyst. Photocatalytic experimental results revealed that Ag-doping TiO2 catalyst shows the enhancement photocatalytic activity.

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Carbon modified TiO2 photocatalysts for water purification

Polish Journal of Chemical Technology ◽

10.2478/v10026-009-0023-0 ◽

2009 ◽

Vol 11 (2) ◽

pp. 46-50 ◽

Cited By ~ 19

Author(s):

Antoni Morawski ◽

Magdalena Janus ◽

Beata Tryba ◽

Masahiro Toyoda ◽

Tomoki Tsumura ◽

...

Keyword(s):

Photocatalytic Activity ◽

Water Purification ◽

Visible Region ◽

Carbon Layer ◽

Photocatalytic Decomposition ◽

Visible Range ◽

Tio2 Photocatalysts ◽

Carbon Doped ◽

Carbon Coated

Carbon modified TiO2 photocatalysts for water purification Carbon can form different structures with TiO2: carbon-doped TiO2, carbon coated TiO2 and composites of TiO2 and carbon. The presence of carbon layer on the surface of TiO2 as well as the presence of porous carbon in the composites with TiO2 can increase the concentration of organic pollutants on the surface of TiO2, facilitating the contact of the reactive species with the organic molecules. Carbon-doped TiO2 can extend the absorption of the light to the visible region by the narrowing of the band gap and makes the photocatalysts active under visible light irradiation. TiO2 loaded carbon can also work as a photocatalyst, on which the molecules are adsorbed in the pores of carbon and then they undergo the photocatalytic decomposition with UV irradiation. Enhanced photocatalytic activity for the destruction of some organic compounds in water was noticed on the carbon coated TiO2 and TiO2 loaded activated carbon, mostly because of the adsorptive role of carbon. However, in carbon-doped TiO2, the role of carbon is somewhat different, the replacement of carbon atom with Ti or oxygen and formation of oxygen vacancies are responsible for extending its photocatalytic activity towards the visible range.

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Optical Properties of Linoleic Acid Protected Gold Nanoparticles

Journal of Nanomaterials ◽

10.1155/2011/630834 ◽

2011 ◽

Vol 2011 ◽

pp. 1-4 ◽

Cited By ~ 12

Author(s):

Ratan Das ◽

Siddartha S. Nath ◽

Ramendu Bhattacharjee

Keyword(s):

Gold Nanoparticles ◽

Linoleic Acid ◽

Fluorescence Spectra ◽

Au Nanoparticles ◽

Chemical Reduction ◽

Colloidal Dispersion ◽

Visible Range ◽

Absorption Bands ◽

Transmission Electron ◽

Vis Spectroscopy

Linoleic acid-protected gold nanoparticles have been synthesized through the chemical reduction of tetrachloroaurate ions by ethanol in presence of sodium linoleate. The structure of these nanoparticles is investigated using transmission electron microscopy, which shows that the Au nanoparticles are spherical in shape with a narrow size distribution which ranges from 8 to 15 nm. Colloidal dispersion of gold nanoparticles in cyclohexane exhibits absorption bands in the ultraviolet-visible range due to surface plasmon resonance, with absorption maximum at 530 nm. Fluorescence spectra of gold nanoparticles also show an emission peak at 610 nm when illuminated at 450 nm. UV-Vis spectroscopy reveals that these nanoparticles remain stable for 10 days.

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Perovskite-structured CaTiO3 coupled with g-C3N4 as a heterojunction photocatalyst for organic pollutant degradation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.62 ◽

2018 ◽

Vol 9 ◽

pp. 671-685 ◽

Cited By ~ 53

Author(s):

Ashish Kumar ◽

Christian Schuerings ◽

Suneel Kumar ◽

Ajay Kumar ◽

Venkata Krishnan

Keyword(s):

Photocatalytic Activity ◽

Organic Pollutant ◽

Visible Region ◽

Active Species ◽

Sunlight Irradiation ◽

Organic Pollutant Degradation ◽

Mixing Method ◽

Plausible Mechanism ◽

Uv Visible ◽

Degradation Of Pollutants

A novel graphitic carbon nitride (g-C3N4)–CaTiO3 (CTCN) organic–inorganic heterojunction photocatalyst was synthesized by a facile mixing method, resulting in the deposition of CaTiO3 (CT) nanoflakes onto the surface of g-C3N4 nanosheets. The photocatalytic activity of the as-synthesized heterojunction (along with the controls) was evaluated by studying the degradation of an aqueous solution of rhodamine B (RhB) under UV, visible and natural sunlight irradiation. The CTCN heterojunction with 1:1 ratio of g-C3N4/CT showed the highest photocatalytic activity under sunlight irradiation and was also demonstrated to be effective for the degradation of a colorless, non-photosensitizing pollutant, bisphenol A (BPA). The superior photocatalytic performance of the CTCN heterojunction could be attributed to the appropriate band positions, close interfacial contact between the constituents and extended light absorption (both UV and visible region), all of which greatly facilitate the transfer of photogenerated charges across the heterojunction and inhibit their fast recombination. In addition, the two-dimensional (2D) morphology of g-C3N4nanosheets and CT nanoflakes provides enough reaction sites due to their larger surface area and enhances the overall photocatalytic activity. Furthermore, the active species trapping experiments validate the major role played by superoxide radicals (O2 −•) in the degradation of pollutants. Based on scavenger studies and theoretically calculated band positions, a plausible mechanism for the photocatalytic degradation of pollutants has been proposed and discussed.

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Uniform SnO2 Hexagonal Prisms with Enhanced Photocatalytic Performance

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2021.2973 ◽

2021 ◽

Vol 16 (4) ◽

pp. 624-629

Author(s):

Yingxin Zhang ◽

Xiaoxiong Song ◽

Li Cui

Keyword(s):

Photocatalytic Activity ◽

Organic Pollutants ◽

Uv Irradiation ◽

Potential Application ◽

Tin Dioxide ◽

Photocatalytic Performance ◽

Organic Dyes ◽

Hydrothermal Route ◽

One Step

In this work, SnO2 hexagonal prisms are successfully prepared by a simple one-step hydrothermal route. The photocatalytic activity of the synthesized product is studied through the degradation of several organic dyes. It shows that eosin red solution is almost degraded after 25 min with UV irradiation. The photodegradation of SnO2 samples with different morphologies and commercial tin dioxide powders are also compared. The as-prepared products exhibit excellent photocatalytic stability, revealing its potential application in the removal of organic pollutants from wastewater.

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Electrospun-based TiO2 nanofibers for organic pollutant photodegradation: a comprehensive review

Reviews in Chemical Engineering ◽

10.1515/revce-2020-0022 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Khee Chung Hui ◽

Hazwani Suhaimi ◽

Nonni Soraya Sambudi

Keyword(s):

Visible Light ◽

Organic Pollutants ◽

Organic Pollutant ◽

Hollow Fibers ◽

Promising Alternative ◽

Tio2 Nanofibers ◽

As Doping ◽

Secondary Pollutants ◽

Photocatalytic Reactors ◽

Light Area

Abstract Titanium dioxide (TiO2) is commonly used as a photocatalyst in the removal of organic pollutants. However, weaknesses of TiO2 such as fast charge recombination and low visible light usage limit its industrial application. Furthermore, photocatalysts that are lost during the treatment of pollutants create the problem of secondary pollutants. Electrospun-based TiO2 fiber is a promising alternative to immobilize TiO2 and to improve its performance in photodegradation. Some strategies have been employed in fabricating the photocatalytic fibers by producing hollow fibers, porous fibers, composite TiO2 with magnetic materials, graphene oxide, as well as doping TiO2 with metal. The modification of TiO2 can improve the absorption of TiO2 to the visible light area, act as an electron acceptor, provide large surface area, and promote the phase transformation of TiO2. The improvement of TiO2 properties can enhance carrier transfer rate which reduces the recombination and promotes the generation of radicals that potentially degrade organic pollutants. The recyclability of fibers, calcination effect, photocatalytic reactors used, operation parameters involved in photodegradation as well as the commercialization potential of TiO2 fibers are also discussed in this review.

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