Insights into Biodegradable Polymer-Supported Titanium Dioxide Photocatalysts for Environmental Remediation

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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Possibilities of using biodegradable polymeric materials in the agricultural sector

Elektrotekhnologii i elektrooborudovanie v APK ◽

10.22314/2658-4859-2020-67-2-115-120 ◽

2020 ◽

Vol 67 (2) ◽

pp. 115-120

Author(s):

Raisa A. Alekhina ◽

Victoriya E. Slavkina ◽

Yuliya A. Lopatina

Keyword(s):

Mechanical Properties ◽

Biodegradable Polymers ◽

Biodegradable Polymer ◽

Agricultural Sector ◽

Polymeric Materials ◽

Polymer Materials ◽

Limiting Factors ◽

Research Purpose ◽

Biodegradable Materials ◽

Advantages And Disadvantages

The article presents options for recycling polymers. The use of biodegradable materials is promising. This is a special class of polymers that can decompose under aerobic or anaerobic conditions under the action of microorganisms or enzymes forming natural products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts. (Research purpose) The research purpose is in reviewing biodegradable materials that can be used for the manufacture of products used in agriculture. (Materials and methods) The study are based on open information sources containing information about biodegradable materials. Research methods are collecting, studying and comparative analysis of information. (Results and discussion) The article presents the advantages and disadvantages of biodegradable materials, mechanical properties of the main groups of biodegradable polymers. The article provides a summary list of agricultural products that can be made from biodegradable polymer materials. It was found that products from the general group are widely used in agriculture. Authors have found that products from a special group can only be made from biodegradable polymers with a controlled decomposition period in the soil, their use contributes to increasing the productivity of crops. (Conclusions) It was found that biodegradable polymer materials, along with environmental safety, have mechanical properties that allow them producing products that do not carry significant loads during operation. We have shown that the creation of responsible products (machine parts) from biodegradable polymers requires an increase in their strength properties, which is achievable by creating composites based on them. It was found that the technological complexity of their manufacture and high cost are the limiting factors for the widespread use of biodegradable polymers at this stage.

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Suitability of Different Titanium Dioxide Nanotube Morphologies for Photocatalytic Water Treatment

Nanomaterials ◽

10.3390/nano11030708 ◽

2021 ◽

Vol 11 (3) ◽

pp. 708

Author(s):

Clayton Farrugia ◽

Alessandro Di Mauro ◽

Frederick Lia ◽

Edwin Zammit ◽

Alex Rizzo ◽

...

Keyword(s):

Antibacterial Activity ◽

Titanium Dioxide ◽

Water Treatment ◽

Environmental Remediation ◽

Survival Rates ◽

Bacterial Survival ◽

Nanotubular Structure ◽

Excellent Activity ◽

Uva Light ◽

High Degree

Photocatalysis has long been touted as one of the most promising technologies for environmental remediation. The ability of photocatalysts to degrade a host of different pollutants, especially recalcitrant molecules, is certainly appealing. Titanium dioxide (TiO2) has been used extensively for this purpose. Anodic oxidation allows for the synthesis of a highly ordered nanotubular structure with a high degree of tunability. In this study, a series of TiO2 arrays were synthesised using different electrolytes and different potentials. Mixed anatase-rutile photocatalysts with excellent wettability were achieved with all the experimental iterations. Under UVA light, all the materials showed significant photoactivity towards different organic pollutants. The nanotubes synthesised in the ethylene glycol-based electrolyte exhibited the best performance, with near complete degradation of all the pollutants. The antibacterial activity of this same material was similarly high, with extremely low bacterial survival rates. Increasing the voltage resulted in wider and longer nanotubes, characteristics which increase the level of photocatalytic activity. The ease of synthesis coupled with the excellent activity makes this a viable material that can be used in flat-plate reactors and that is suitable for photocatalytic water treatment.

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Nanocomposites containing titanium dioxide for environmental remediation

Designed Monomers & Polymers ◽

10.1080/15685551.2021.1876322 ◽

2021 ◽

Vol 24 (1) ◽

pp. 22-45

Author(s):

Soad Z. Alsheheri

Keyword(s):

Titanium Dioxide ◽

Environmental Remediation

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Effect of Cold Drawing on Mechanical Properties of Biodegradable Fibers

Journal of Applied Biomaterials & Functional Materials ◽

10.5301/jabfm.5000328 ◽

2017 ◽

Vol 15 (1) ◽

pp. 70-76 ◽

Cited By ~ 5

Author(s):

Francesco Paolo La Mantia ◽

Manuela Ceraulo ◽

Maria Chiara Mistretta ◽

Marco Morreale

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Biodegradable Polymers ◽

Biodegradable Polymer ◽

Cold Drawing ◽

Thermal Characterization ◽

Systematic Investigation ◽

Thermomechanical Properties ◽

Polymer Systems ◽

The Impact

Purpose Biodegradable polymers are currently gaining importance in several fields, because they allow mitigation of the impact on the environment related to disposal of traditional, nonbiodegradable polymers, as well as reducing the utilization of oil-based sources (when they also come from renewable resources). Fibers made of biodegradable polymers are of particular interest, though, it is not easy to obtain polymer fibers with suitable mechanical properties and to tailor these to the specific application. The main ways to tailor the mechanical properties of a given biodegradable polymer fiber are based on crystallinity and orientation control. However, crystallinity can only marginally be modified during processing, while orientation can be controlled, either during hot drawing or cold stretching. In this paper, a systematic investigation of the influence of cold stretching on the mechanical and thermomechanical properties of fibers prepared from different biodegradable polymer systems was carried out. Methods Rheological and thermal characterization helped in interpreting the orientation mechanisms, also on the basis of the molecular structure of the polymer systems. Results and conclusions It was found that cold drawing strongly improved the elastic modulus, tensile strength and thermomechanical resistance of the fibers, in comparison with hot-spun fibers. The elastic modulus showed higher increment rates in the biodegradable systems upon increasing the draw ratio.

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Modification of the titanium implants surface with TiO2 coatings obtained by sol-gel method via dip-coating

MATEC Web of Conferences ◽

10.1051/matecconf/201822603014 ◽

2018 ◽

Vol 226 ◽

pp. 03014

Author(s):

Vitaly A. Tarala ◽

Alexander A. Dolgalev ◽

Alexander A. Kravtsov ◽

Irina S. Chikulina ◽

Boris V. Bukhalov

Keyword(s):

Titanium Dioxide ◽

Sol Gel ◽

Dip Coating ◽

Titanium Implants ◽

High Rate ◽

Drawing Rate ◽

Gel Method ◽

Sol Gel Method ◽

Automated Method ◽

Tio2 Coatings

Within the framework of the study, TiO2 coatings were obtained by sol-gel method via dip-coating. For the films obtaining, manual drawing the substrate from the solution at a relatively high rate of 30 mm / min and automated drawing from the solution at low drawing rates (from 1 to 10 mm / min) were used. The morphology of coatings has been studied by scanning electron microscopy. The influence of the mode and the rate of drawing of the substrate from the solution on the films morphology was demonstrated. Analysis of the data showed, that the surface morphology of the coatings obtained at lower drawing rates by an automated method is much more homogeneous - the titanium dioxide films completely repeats the topography of the substrate surface, there are practically no fissures. Qualitative coatings of titanium dioxide, completely replicating the surface relief of the substrate, can be obtained by this method. Selection of the substrate drawing rate allows reducing the influence of the substrate topography and avoiding the appearance of crystallization centers, and as a consequence, the appearance of defects in the morphology of coatings, such as fissures or microparticles.

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Features of Fabrication of Titanium Dioxide Based Coatings for Non-Lithographic Template Electrochemical Synthesis of Micron Metal Particle Arrays

Gels ◽

10.3390/gels7040202 ◽

2021 ◽

Vol 7 (4) ◽

pp. 202

Author(s):

Andrey Yu Arbenin ◽

Elena G. Zemtsova ◽

Evgeniy V. Orekhov ◽

Daria N. Sokolova ◽

Polina I. Baburova ◽

...

Keyword(s):

Titanium Dioxide ◽

Template Synthesis ◽

Electrochemical Synthesis ◽

Sol Gel ◽

Dip Coating ◽

Element Distribution ◽

Micro Particles ◽

Methods Of Synthesis ◽

Mechanisms Of Formation ◽

Xerogel Films

This work is devoted to the development of non-lithographic template methods of synthesis. These methods have a significant advantage in terms of structure formation: there is no need to design and produce masks, which greatly simplifies the process, and more of them can work with nonplanar substrates. The purpose of this study was to reveal the conditions for the synthesis of titanium dioxide xerogel films of different topologies as well as to develop a technique for non-lithographic template electrochemical synthesis of micron metal particles arrays and to study the structure of the resulting coatings. The films were deposited on the surface of substrates via dip coating. Specific topology of the films was achieved by template sol-gel synthesis. Their structures were analyzed by SEM and XRD. Template synthesis of metal micro particles were realized by pulsed electrochemical deposition of metals into the perforations of xerogel films. Obtained materials were analyzed by SEM and XRD; the element distribution on the surface was determined by the EDS detector of SEM. Based on the analysis results, we suggest the mechanisms of formation of the xerogel topology and proved the efficiency of pulsed electrodeposition for template synthesis of micron particles arrays.

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Titanium Dioxide Coatings Doubly-Doped with Ca and Ag Ions as Corrosion Resistant, Biocompatible, and Bioactive Materials for Medical Applications

Coatings ◽

10.3390/coatings10020169 ◽

2020 ◽

Vol 10 (2) ◽

pp. 169

Author(s):

Barbara Burnat ◽

Patrycja Olejarz ◽

Damian Batory ◽

Michal Cichomski ◽

Marta Kaminska ◽

...

Keyword(s):

Titanium Dioxide ◽

Sol Gel ◽

Immersion Test ◽

Dip Coating ◽

Biological Properties ◽

Biological Evaluation ◽

Molar Ratio ◽

Bioactive Materials ◽

Corrosion Resistant ◽

X Ray

The aim of this study was to develop a multifunctional biomedical coating that is highly corrosion resistant, biocompatible, and reveals the bioactive properties. For that purpose, titanium dioxide coatings doubly-doped with Ca and Ag ions were deposited by dip-coating onto M30NW biomedical steel. The influence of different ratios of Ca and Ag dopants on morphology, surface structure, corrosion resistance, bioactivity, wettability, and biological properties of TiO2-based sol-gel coatings was studied and discussed. Comprehensive measurements were performed including atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray reflectivity (XRR), corrosion tests, immersion test, contact angle, as well as biological evaluation. The obtained results confirmed that anatase-based coatings containing Ca and Ag ions, independently of their molar ratio in the coating, are anticorrosive, hydrophilic, and bioactive. The results of the biological evaluation indicated that investigated coatings are biocompatible and do not reduce the proliferation ability of the osteoblasts cells.

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Fabrication of polysiloxane-modified polyurethane sponge as low-cost organics/water separation and selective absorption material

Water Science & Technology ◽

10.2166/wst.2016.348 ◽

2016 ◽

Vol 74 (8) ◽

pp. 1936-1945 ◽

Cited By ~ 2

Author(s):

Zhengshan Cui ◽

Wanxia He ◽

Jun Liu ◽

Wei Wei ◽

Liang Jiang ◽

...

Keyword(s):

Contact Angle ◽

Mechanical Stability ◽

Low Cost ◽

Sol Gel ◽

Dip Coating ◽

Selective Absorption ◽

Large Area ◽

Water Separation ◽

Good Thermal Stability ◽

Polyurethane Sponge

Through sol-gel and dip-coating processes, commercial polyurethane sponge modified by polysiloxane was fabricated under low temperature (60 °C) and atmosphere. The contact angle of the obtained polysiloxane/polyurethane sponge is 145 ± 5°. Hence, the polysiloxane/polyurethane sponge could float on water and selectively absorb organics from the surface of the water, indicating simultaneous properties of hydrophobicity and oleophilicity. The absorbent maximum value is 50–150 times of its own weight. The polysiloxane/polyurethane sponge exhibited excellent recyclability, which could be reused by squeezing the sponge due to its high mechanical stability and flexibility. Thermogravimetry-differential thermal analysis test indicated that the polysiloxane/polyurethane sponge exhibited good thermal stability and the stable contact angle of samples tested under increasing temperature indicated its good weather resistance. Due to the commercial property of polyurethane sponge and easy-handling of polysiloxane, the polysiloxane/polyurethane sponge can be easily scaled up to recover a large-area oil spill in water and further work based on the designed equipment has been under consideration.

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Photocatalytic Degradation of Indoor Air Pollutants by Pt-

Journal of Nanomaterials ◽

10.1155/2012/405361 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Gui Bing Hong ◽

Chih Ming Ma

Keyword(s):

Titanium Dioxide ◽

Confidence Interval ◽

Indoor Air ◽

Air Pollutants ◽

Environmental Remediation ◽

Experimental Result ◽

Cosmetic Products ◽

Initial Concentration ◽

Catalyst Type ◽

Indoor Air Pollutants

Titanium dioxide (TiO2) has been extensively studied with regard to its application as the physical sunblock in sunscreen or other cosmetic products, as well as in environmental remediation processes. In this study, the Taguchi method was applied to determine the optimum gaseous DCM (dichloromethane) by Pt-TiO2with different Pt contents. An orthogonal array (L32) experimental design that allows for the simultaneous investigation of the variations of six parameters (light source, catalyst type, initial concentration, retention time, photointensity, and relative humidity) was employed to determine the optimum levels. The value of photointensity was not at a confidence interval. According to the response values and an analysis of variance (ANOVA), an experimental result of 34.7 as the optimum condition is forecast. Although the predetermination of 34.7 is not equal to the experimental value, it is contained within the 90% confidence interval (25.8, 43.6).

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