Fabrication of Silica Microspheres Containing TiO2 or Aluminum Zinc Oxide Nanoparticles via Self-Assembly: Application in Water Purification

In this study, silica micro-particles containing titania (TiO2) or aluminum zinc oxide (AZO) nanopar-ticles were synthesized using emulsion droplets as micro-reactors, for water purification application via photocatalytic decomposition of organic dyes. Towards this end, aqueous silicic acid solution has been emulsified with aqueous dispersion of TiO2 or AZO nanoparticles in a continuous oil phase to form tiny droplets, followed by subsequent self-assembly of the droplets via evaporation. The resulting composite microparticles were controlled to obtain a spherical or porous morphology by adjusting the concentration of the nanoparticle dispersion. As a demonstrative application, the resulting composite micro-particles have been used as photocatalysts for the removal of methylene blue under UV irradiation. In the case of silica microparticles containing AZO nanoparticles, the adsorption of organic pollutants combined with photocatalytic decomposition was found to be effective, and trace amounts of the pollutant remained after the removal process.

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Photocatalytic Decomposition of Organic Dyes Using a Rotating Cylinder System

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19437 ◽

2021 ◽

Vol 21 (8) ◽

pp. 4544-4552

Author(s):

Young-Sang Cho ◽

Sohyeon Sung

Keyword(s):

Rate Constant ◽

Organic Dyes ◽

Outer Cylinder ◽

Rotating Cylinder ◽

Organic Dye ◽

Photocatalytic Decomposition ◽

Nanoparticle Dispersion ◽

Batch Mode ◽

Factors Affecting ◽

Repeated Batch

In this study, a rotating cylinder system was used in the photocatalytic decomposition of organic dyes in aqueous medium for water purification. To this end, the titania nanoparticle dispersion was mixed with an organic dye solution under a rotating inner cylinder at controlled speed. The rate constant was adjusted by changing the speed of rotation to determine the optimal circulating velocity. Since nanoparticle dispersion is a secondary contaminant after wastewater treatment, the titania paste was deposited on the inner surface of the stationary outer cylinder to form a photocatalytic film. During repeated batch-mode operation, the deactivation of the deposited film was analyzed by measuring the rate constant as a function of time. Continuous operation was also used to remove organic dye in the water to study factors affecting the removal efficiency of methylene blue. Higher rotating velocity and slow feed rate facilitated the removal of contaminants via desorption of adsorbed dyes with adequate retention time.

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Engineering the shape of Zinc Oxide crystals via sonochemical or hydrothermal solution-based methods

MRS Proceedings ◽

10.1557/proc-1087-v06-04 ◽

2008 ◽

Vol 1087 ◽

Author(s):

Marco Palumbo ◽

Simon J. Henley ◽

Thierry Lutz ◽

Vlad Stolojan ◽

David Cox ◽

...

Keyword(s):

Zinc Oxide ◽

Self Assembly ◽

Hydrothermal Solution ◽

Good Control ◽

Transparent Conductors ◽

Zno Nanostructures ◽

Large Area ◽

Light Emitting Devices ◽

Wide Range ◽

Solution Methods

AbstractRecent results in the use of Zinc Oxide (ZnO) nano/submicron crystals in fields as diverse as sensors, UV lasers, solar cells, piezoelectric nanogenerators and light emitting devices have reinvigorated the interest of the scientific community in this material. To fully exploit the wide range of properties offered by ZnO, a good understanding of the crystal growth mechanism and related defects chemistry is necessary. However, a full picture of the interrelation between defects, processing and properties has not yet been completed, especially for the ZnO nanostructures that are now being synthesized. Furthermore, achieving good control in the shape of the crystal is also a very desirable feature based on the strong correlation there is between shape and properties in nanoscale materials. In this paper, the synthesis of ZnO nanostructures via two alternative aqueous solution methods - sonochemical and hydrothermal - will be presented, together with the influence that the addition of citric anions or variations in the concentration of the initial reactants have on the ZnO crystals shape. Foreseen applications might be in the field of sensors, transparent conductors and large area electronics possibly via ink-jet printing techniques or self-assembly methods.

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Aqueous Dispersion Polymerization: A New Paradigm for in Situ Block Copolymer Self-Assembly in Concentrated Solution

Journal of the American Chemical Society ◽

10.1021/ja205887v ◽

2011 ◽

Vol 133 (39) ◽

pp. 15707-15713 ◽

Cited By ~ 321

Author(s):

Shinji Sugihara ◽

Adam Blanazs ◽

Steven P. Armes ◽

Anthony J. Ryan ◽

Andrew L. Lewis

Keyword(s):

Block Copolymer ◽

Self Assembly ◽

Dispersion Polymerization ◽

Aqueous Dispersion ◽

New Paradigm ◽

Concentrated Solution

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Electrochemical Self-Assembly of Oriented Zinc Oxide Film from Polyethylene Oxide Containing Electrolyte

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2009.442 ◽

2009 ◽

Vol 9 (3) ◽

pp. 1766-1771 ◽

Cited By ~ 4

Author(s):

Xiaohui Ju ◽

Wei Feng ◽

Akihiko Fujii ◽

Masanori Ozaki

Keyword(s):

Zinc Oxide ◽

Oxide Film ◽

Polyethylene Oxide ◽

Self Assembly ◽

Zinc Oxide Film

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PANI Based Metal Oxide Nanocomposite – A Novel Material for Water Purification

Advances in Nanoscience and Nanotechnology ◽

10.33140/ann.04.02.03 ◽

2020 ◽

Vol 4 (2) ◽

Keyword(s):

Water Purification ◽

Organic Dyes ◽

Polymer Nanocomposite ◽

Combustion Method ◽

Chemical Oxidation ◽

Oxidation Method ◽

Photo Catalyst ◽

Absorbance Spectroscopy ◽

Novel Material ◽

Synthesized Materials

In the present work NiO/ZnO was synthesized from combustion method, polyaniline and the polyaniline based NiO/ZnO using chemical oxidation method. The synthesized materials were characterized using XRD and UV/Vis absorbance spectroscopy. From XRD, the formation of NiO/ZnO was confirmed. The study investigates the applicability of NiO/ZnO Nanocomposite as photo catalyst for the degradation of organic dyes. Results suggested an increase in degradation efficiency in the case of polymer nanocomposite when compared to counter parts.

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Self-assembly Patterning of Nano/micro-particles

KONA Powder and Particle Journal ◽

10.14356/kona.2007004 ◽

2007 ◽

Vol 25 (0) ◽

pp. 2-3

Author(s):

Yoshitake Masuda

Keyword(s):

Self Assembly ◽

Micro Particles

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Rapid Thermal Annealing for Solution Synthesis of Transparent Conducting Aluminum Zinc Oxide Thin Films

Journal of Electronic Materials ◽

10.1007/s11664-017-5704-5 ◽

2017 ◽

Vol 46 (11) ◽

pp. 6609-6616 ◽

Cited By ~ 3

Author(s):

Sana Ullah ◽

Fabio De Matteis ◽

Ivan Davoli

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Thermal Annealing ◽

Rapid Thermal Annealing ◽

Solution Synthesis ◽

Oxide Thin Films ◽

Transparent Conducting ◽

Aluminum Zinc Oxide

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Self-assembly of acacia gum and β-lactoglobulin in aqueous dispersion

Special Publications - Plant Biopolymer Science ◽

10.1039/9781847551672-00111 ◽

2007 ◽

pp. 111-118

Author(s):

C. Schmitt ◽

G. Mekhloufi ◽

J. Hardy ◽

D. Renard ◽

P. Robert

Keyword(s):

Self Assembly ◽

Aqueous Dispersion ◽

Acacia Gum ◽

Β Lactoglobulin

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Self-assembly modification of polyamide membrane by coating titanium dioxide nanoparticles for water treatment applications

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2297 ◽

2019 ◽

Vol 14 (3) ◽

pp. 1

Author(s):

Rosangela Bergamasco ◽

Priscila Ferri Coldebella ◽

Franciele Pereira Camacho ◽

Driano Rezende ◽

Natalia Ueda Yamaguchi ◽

...

Keyword(s):

Tio2 Nanoparticles ◽

Self Assembly ◽

Photocatalytic Performance ◽

Titanium Dioxide Nanoparticles ◽

Photocatalytic Decomposition ◽

High Permeability ◽

Physical Separation ◽

Assembly Method ◽

Wastewater Systems ◽

Polyamide Membrane

This study modified the surface of a commercial polyamide membrane with the deposition of TiO2 nanoparticles by the self-assembly method under pressure with high permeability and photocatalytic activity. Changes in membrane characteristics and its performance for photocatalytic properties were evaluated. The results indicated that both membrane hydrophilicity and photocatalytic performance were significantly improved by the presence of TiO2 nanoparticles applied under a pressure of 1 bar. The deposition of the TiO2 particles under pressure was able to maintain the particles on the surface of the membranes and their photocatalytic capacity for three cycles of use. The prepared TiO2 photocatalytic membrane presented a great potential for wastewater treatment and for reuse wastewater systems due its ability to remove methylene blue (MB) dye solution by photocatalytic decomposition and physical separation.

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