Application of TiO2 photocatalysts hybridized with carbonaceous for degradation of pharmaceuticals

During the past two decades, immobilization of titanium dioxide (TiO2), a well-known photocatalyst, on several polymeric substrates has extensively gained ground since it limits the need of post-treatment separation stages. Taking into account the numerous substrates tested for supporting TiO2 photocatalysts, the use of biodegradable polymer seems a hopeful option owing to its considerable merits, including the flexible nature, low price, chemical inertness, mechanical stability and wide feasibility. The present review places its emphasis on recently published research articles (2011–2021) and exhibits the most innovative studies facilitating the eco-friendly biodegradable polymers to fabricate polymer-based photocatalysts, while the preparation details, photocatalytic performance and reuse of the TiO2/polymer photocatalysts is also debated. The biodegradable polymers examined herein comprise of chitosan (CS), cellulose, alginate, starch, poly(lactid acid) (PLA), polycaprolactone (PCL) and poly(lactide-co-glycolide) (PLGA), while an emphasis on the synthetical pathway (dip-coating, electrospinning, etc.) of the photocatalysts is provided.

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Eco-Friendly Colloidal Aqueous Sol-Gel Process for TiO2 Synthesis: The Peptization Method to Obtain Crystalline and Photoactive Materials at Low Temperature

Catalysts ◽

10.3390/catal11070768 ◽

2021 ◽

Vol 11 (7) ◽

pp. 768

Author(s):

Julien G. Mahy ◽

Louise Lejeune ◽

Tommy Haynes ◽

Stéphanie D. Lambert ◽

Raphael Henrique Marques Marcilli ◽

...

Keyword(s):

Organic Pollutant ◽

Sol Gel ◽

Synthesis Method ◽

Specific Treatment ◽

High Specific Surface Area ◽

Crystalline Phases ◽

Tio2 Photocatalysts ◽

Tio2 Anatase ◽

Synthesis Parameters ◽

Calcination Step

This work reviews an eco-friendly process for producing TiO2 via colloidal aqueous sol–gel synthesis, resulting in crystalline materials without a calcination step. Three types of colloidal aqueous TiO2 are reviewed: the as-synthesized type obtained directly after synthesis, without any specific treatment; the calcined, obtained after a subsequent calcination step; and the hydrothermal, obtained after a specific autoclave treatment. This eco-friendly process is based on the hydrolysis of a Ti precursor in excess of water, followed by the peptization of the precipitated TiO2. Compared to classical TiO2 synthesis, this method results in crystalline TiO2 nanoparticles without any thermal treatment and uses only small amounts of organic chemicals. Depending on the synthesis parameters, the three crystalline phases of TiO2 (anatase, brookite, and rutile) can be obtained. The morphology of the nanoparticles can also be tailored by the synthesis parameters. The most important parameter is the peptizing agent. Indeed, depending on its acidic or basic character and also on its amount, it can modulate the crystallinity and morphology of TiO2. Colloidal aqueous TiO2 photocatalysts are mainly being used in various photocatalytic reactions for organic pollutant degradation. The as-synthesized materials seem to have equivalent photocatalytic efficiency to the photocatalysts post-treated with thermal treatments and the commercial Evonik Aeroxide P25, which is produced by a high-temperature process. Indeed, as-prepared, the TiO2 photocatalysts present a high specific surface area and crystalline phases. Emerging applications are also referenced, such as elaborating catalysts for fuel cells, nanocomposite drug delivery systems, or the inkjet printing of microstructures. Only a few works have explored these new properties, giving a lot of potential avenues for studying this eco-friendly TiO2 synthesis method for innovative implementations.

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Highly dispersed MoSx nanodot-modified TiO2 photocatalysts: vitamin C-mediated synthesis and improved H2 evolution activity

Journal of Materials Chemistry C ◽

10.1039/d0tc06095j ◽

2021 ◽

Author(s):

Jiangyuan He ◽

Wei Zhong ◽

Ying Xu ◽

Jiajie Fan ◽

Huogen Yu ◽

...

Keyword(s):

Vitamin C ◽

H2 Evolution ◽

Tio2 Photocatalysts ◽

Highly Dispersed

Highly dispersed MoSx nanodots are loaded on the TiO2 surface via a thin-layered carbon supporter to attain a significantly boosted photocatalytic H2-evolution performance by applying a vitamin C-mediated method.

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Magnetic Ni-Doped TiO2 Photocatalysts for Disinfection of Escherichia coli Bacteria

Journal of Electronic Materials ◽

10.1007/s11664-020-08699-2 ◽

2021 ◽

Author(s):

Khang Cao Nguyen ◽

Nghia Manh Nguyen ◽

Van Quoc Duong ◽

Khanh Van Nguyen ◽

Hung Manh Nguyen ◽

...

Keyword(s):

Escherichia Coli ◽

Tio2 Photocatalysts ◽

Doped Tio2 ◽

Escherichia Coli Bacteria

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Double-Nozzle Flame Spray Pyrolysis as a Potent Technology to Engineer Noble Metal-TiO2 Nanophotocatalysts for Efficient H2 Production

Energies ◽

10.3390/en14040817 ◽

2021 ◽

Vol 14 (4) ◽

pp. 817

Author(s):

Maria Solakidou ◽

Yiannis Georgiou ◽

Yiannis Deligiannakis

Keyword(s):

Spray Pyrolysis ◽

Noble Metal ◽

H2 Production ◽

Flame Spray Pyrolysis ◽

Flame Spray ◽

Scale Production ◽

Efficient Technology ◽

Tio2 Photocatalysts ◽

Surface Dispersion ◽

Tio2 Matrix

Noble metal-TiO2 nanohybrids, NM0-TiO2, (NM0 = Pt0, Pd0, Au0, Ag0) have been engineered by One-Nozzle Flame Spray Pyrolysis (ON-FSP) and Double-Nozzle Flame Spray Pyrolysis (DN-FSP), by controlling the method of noble metal deposition to the TiO2 matrix. A comparative screening of the two FSP methods was realized, using the NM0-TiO2 photocatalysts for H2 production from H2O/methanol. The results show that the DN-FSP process allows engineering of more efficient NM0-TiO2 nanophotocatalysts. This is attributed to the better surface-dispersion and narrower size-distribution of the noble metal onto the TiO2 matrix. In addition, DN-FSP process promoted the formation of intraband states in NM0-TiO2, lowering the band-gap of the nanophotocatalysts. Thus, the present study demonstrates that DN-FSP process is a highly efficient technology for fine engineering of photocatalysts, which adds up to the inherent scalability of Flame Spray Pyrolysis towards industrial-scale production of nanophotocatalysts.

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Modified-TiO2 Photocatalyst Supported on β-SiC Foams for the Elimination of Gaseous Diethyl Sulfide as an Analog for Chemical Warfare Agent: Towards the Development of a Photoreactor Prototype

Catalysts ◽

10.3390/catal11030403 ◽

2021 ◽

Vol 11 (3) ◽

pp. 403

Author(s):

Armelle Sengele ◽

Didier Robert ◽

Nicolas Keller ◽

Valérie Keller

Keyword(s):

Photocatalytic Oxidation ◽

Chemical Warfare Agents ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Diethyl Sulfide ◽

Tio2 Photocatalysts ◽

Doped Tio2 ◽

Model Molecule ◽

Warfare Agents ◽

Oxidation Efficiency

In the context of the increase in chemical threat due to warfare agents, the development of efficient methods for destruction of Chemical Warfare Agents (CWAs) are of first importance both for civilian and military purposes. Amongst possible methods for destruction of CWAs, photocatalytic oxidation is an alternative one. The present paper reports on the preparation of Ta and Sn doped TiO2 photocatalysts immobilized on β-SiC foams for the elimination of diethyl sulfide (DES) used as a model molecule mimicking Yperite (Mustard Gas) in gaseous phase. Photo-oxidation efficiency of doped TiO2 catalyst has been compared with TiO2-P25. Here, we demonstrate that the Sn doped-TiO2 with a Polyethylene glycol (PEG)/TiO2 ratio of 7 exhibits the best initial activity (up to 90%) but is deactivates more quickly than Ta doped-TiO2 (40% after 800 min). The activity of the catalysts is strongly influenced by the adsorption properties of the support, as β-SiC foams adsorb DES and other sulfur compounds. This adsorption makes it possible to limit the poisoning of the catalysts and to maintain an acceptable conversion rate even after ten hours under continuous DES flow. Washing with NaOH completely regenerates the catalyst after a firs treatment and even seems to “wash” it by removing impurities initially present on the foams.

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Revisiting Pt/TiO2 photocatalysts for thermally assisted photocatalytic reduction of CO2

Nanoscale ◽

10.1039/c9nr09743k ◽

2020 ◽

Vol 12 (13) ◽

pp. 7000-7010 ◽

Cited By ~ 12

Author(s):

Fei Yu ◽

Changhua Wang ◽

He Ma ◽

Miao Song ◽

Dongsheng Li ◽

...

Keyword(s):

Pt Nanoparticles ◽

Photocatalytic Reduction ◽

Tio2 Photocatalysts ◽

Reduction Of Co2

Ultrasonic disordering of a TiO2 surface results in smaller Pt nanoparticles and promotes the thermally assisted photocatalytic reduction of CO2, yielding higher CH4 selectivity.

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