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Development Of Nanosized Tio2 Powder Photocatalyst And Its Application For Bacteria Killing
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Book Synopsis Development of Nanosized TiO2 Powder Photocatalyst and Its Application for Bacteria Killing by : Farah Diana Binti Mohd Daud
Download or read book Development of Nanosized TiO2 Powder Photocatalyst and Its Application for Bacteria Killing written by Farah Diana Binti Mohd Daud and published by . This book was released on 2011 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book TiO2 Nanoparticles written by Aiguo Wu and published by John Wiley & Sons. This book was released on 2020-06-02 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique book that summarizes the properties, toxicology, and biomedical applications of TiO2-based nanoparticles Nanotechnology is becoming increasingly important for products used in our daily lives. Nanometer-sized titanium dioxide (TiO2) are widely used in industry for different purposes, such as painting, sunscreen, printing, cosmetics, biomedicine, and so on. This book summarizes the advances of TiO2 based nanobiotechnology and nanomedicine, covering materials properties, toxicological research, and biomedical application, such as antibacter, biosensing, and cancer theranostics. It uniquely integrates the TiO2 applications from physical properties, toxicology to various biomedical applications, and includes black TiO2 based cancer theranostics. Beginning with a comprehensive introduction to the properties and applications of nanoparticles, TiO2 Nanoparticles: Applications in Nanobiotechnology, Theranostics and Nanomedicine offers chapters on: Toxicity of TiO2 Nanoparticles; Antibacterial Applications of TiO2 Nanoparticles; Surface Enhanced Raman Spectrum of TiO2 Nanoparticle for Biosensing (TiO2 Nanoparticle Served as SERS Sensing Substrate); TiO2 as Inorganic Photosensitizer for Photodynamic Therapy; Cancer Theranostics of Black TiO2 Nanoparticles; and Neurodegenerative Disease Diagnostics and Therapy of TiO2-Based Nanoparticles. This title: -Blends the physical properties, toxicology of TiO2 nanoparticles to the many biomedical applications -Includes black TiO2 based cancer theranostics in its coverage -Appeals to a broad audience of researchers in academia and industry working on nanomaterials-based biosensing, drug delivery, nanomedicine TiO2 Nanoparticles: Applications in Nanobiotechnology, Theranostics and Nanomedicine is an ideal book for medicinal chemists, analytical chemists, biochemists, materials scientists, toxicologists, and those in the pharmaceutical industry.
Book Synopsis Development of SiO2/TiO2 Photocatalyst with Nanosized TiO2 Crystals by : Vamsi Jamalapuram
Download or read book Development of SiO2/TiO2 Photocatalyst with Nanosized TiO2 Crystals written by Vamsi Jamalapuram and published by . This book was released on 2006 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Advances in Photocatalytic Disinfection by : Taicheng An
Download or read book Advances in Photocatalytic Disinfection written by Taicheng An and published by Springer. This book was released on 2016-11-21 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest results related to photocatalytic inactivation/killing of microorganisms, which is a promising alternative disinfection method that produces less or even no disinfection byproduct. The book is divided into 13 chapters, which introduce readers to the latest developments in the photocatalytic disinfection of microorganisms, examine essential photocatalytic (PC) and photoelectrocatalytic (PEC) disinfection studies, and forecast and make recommendations for the further development of PC and PEC disinfection. Bringing together contributions by various leading research groups worldwide, it offers a valuable resource for researchers and the industry alike, as well as the general public. Taicheng An, PhD, is Chair Professor and Director at the Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, China. Huijun Zhao, PhD, is Chair Professor and Director at the Centre for Clean Environment and Energy & Griffith School of Environment, Griffith University, Australia. Po Keung Wong, PhD, is a Professor at the School of Life Sciences, the Chinese University of Hong Kong, Hong Kong SAR, China.
Book Synopsis Design and Development of a New Generation of UV-visible-light-driven Nanosized Codoped Titanium Dioxide Photocatalysts and Biocides/sporocides, and Environmental Applications by :
Download or read book Design and Development of a New Generation of UV-visible-light-driven Nanosized Codoped Titanium Dioxide Photocatalysts and Biocides/sporocides, and Environmental Applications written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: For solar environmental remediation, a new generation of nanosized (10 nm) titanium dioxide photocatalysts codoped with metals and nonmetals, or metals only were prepared by the xero-gel and aero-gel methods. For silver or cobalt-based xero-gel titanium dioxide photocatalysts, photoactivities tests revealed that codoping of titanium dioxide with a metal (1% Ag or 2% Co) and nonmetals (carbon and sulfur) is necessary to achieve high-activities for acetaldehyde degradation under visible light (wavelength 420 nm). It was concluded that high visible-light-activities for acetaldehyde degradation over codoped titanium dioxide were attributed to an interplay of anatase crystallinity, high-surface area, reduced band-gap (3.0 eV), uniform dispersion of doped metal ions, and suppressed recombination rate of photogenerated electron-hole pairs. Moreover, the nature and amount of codoped metals play a significant role in visible-light-induced photocatalysis. Metals (Al, Ga, and In) doped/codoped titanium dioxide photocatalysts were prepared by the aero-gel method. The photocatalytic studies showed that activities of metal doped/codoped photocatalysts under UV light (wavelength 400 nm) were found to be dependent on pollutants. Indium demonstrated beneficial effects in both textural and photocatalytic properties. Gallium and indium codoped titanium dioxide photocatalysts displayed even better performance in the CO oxidation reaction under UV light. Notably, titanium dioxide codoped with Ga, In, and Pt, exhibited unique photoactivities for the CO oxidation under both UV and visible light irradiation, indicating that this system could have promise for the water-gas shift reaction for hydrogen production. Silver-based nanostructured titanium dioxide samples were developed for killing human pathogens (Escherichia coli cells and Bacillus subtilis spores). Biocidal tests revealed that silver, carbon, and sulfur codoped titanium dioxide nanoparticles (
Book Synopsis Environmentally Benign Photocatalysts by : Masakazu Anpo
Download or read book Environmentally Benign Photocatalysts written by Masakazu Anpo and published by Springer Science & Business Media. This book was released on 2010-11-10 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few decades, mankind has observed an unprecedented and remarkable growth in industry, resulting in a more prosperous lifestyle for peoples of many countries. In developing countries, however, explosive industrial growth is just now beginning to raise the living standards of the people. Most industries, especially in these developing countries, are still powered by the burning of fossil fuels; con- quently, a lack of clean energy resources has caused environmental pollution on an unprecedented large and global scale. Toxic wastes have been relentlessly released into the air and water leading to serious and devastating environmental and health problems while endangering the planet and life itself with the effects of global warming. To address these urgent environmental issues, new catalytic and photocatalytic processes as well as open-atmospheric systems are presently being developed that can operate at room temperature while being totally clean and ef?cient and thus environmentally harmonious. Essential to technologies harnessing the abundant solar energy that reaches the earth are the highly functional photocatalytic proce- es that can utilize not only UV light, but also visible light.
Book Synopsis Photocatalytic Activity Enhancement of Titanium Dioxide Nanoparticles by : Mohamed A. Barakat
Download or read book Photocatalytic Activity Enhancement of Titanium Dioxide Nanoparticles written by Mohamed A. Barakat and published by Springer. This book was released on 2015-10-26 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this brief, a comprehensive review of the UV/visible-TiO2 photocatalytic oxidation process is presented with an insight into the mechanisms involved, the role of titanium dioxide as a catalyst, irradiation sources, types of reactors, and a comparison between various modes of TiO2 application. An overview of the development and enhancement of the activity of TiO2 nanoparticles in photocatalysis is presented. The topics covered include a detailed look at the unique properties of the TiO2 nanoparticles and their relationship to photocatalytic properties. The utilization of the TiO2 nanoparticles as photocatalysts, in the non-doped and doped forms is also reviewed. Finally, the use of modified TiO2 nanoparticles has made a significant contribution in providing definitive mechanistic information regarding the visible light photocatalytic processes.
Book Synopsis "Synthesis of TiO2 based nanoparticles for photocatalytic applications by : Kranthi Kumar Akurati
Download or read book "Synthesis of TiO2 based nanoparticles for photocatalytic applications written by Kranthi Kumar Akurati and published by Cuvillier Verlag. This book was released on 2008-10-27 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various gas phase synthesis routes have been employed to produce TiO2 based nanoparticles for photocatalytic applications. Synthesis routes have been selected depending up on the feasibility/constraints of the particular process to produce a given kind of material. The first attempt at producing the photocatalysts involved the synthesis of pure TiO2 nanoparticles by a flame aerosol process. The growth behaviour of TiO2 particles which has significant influence on their crystallinity and surface area, has been controlled by varying the process parameters and selecting suitable flame configurations. An existing method to determine the crystallinity of the powder has been modified which facilitates comparison of the degree of crystallinity of the nanoparticles synthesized by various methods. Resultant TiO2 nanoparticles were characterized by X-ray diffraction (XRD) and nitrogen physisorption to determine the degree of crystallinity quantitatively and surface area, respectively, and the decomposition rate of an industrial dye, methylene blue, has been taken as the measure of the photocatalytic activity (PCA). The importance of an optimum combination of crystallinity and surface area for improved PCA has been shown by comparing the PCA of the as-synthesized nanoparticles with commercial TiO2 (Degussa P25). By depositing another semiconductor material on TiO2, PCA of the resultant composite photocatalyst can be improved due to the effective separation of the charge carriers. The deposited semiconductor has been chosen by virtue of its conduction band potential which should be higher than that of the TiO2. Accordingly, SnO2/TiO2 composite nanoparticles have been synthesized in a single-step by feeding evaporated precursor mixtures into an atmospheric pressure diffusion flame. For the lowest concentration (3.4 mol %) of SnO2 employed in this study anatase phase of TiO2 is stabilized, while segregation of SnO2 is seen at medium (6.9 to 12.4 mol %) and high concentrations (20.3 mol %). Though the equilibrium phase diagram predicts complete solubility of one oxide in another at all compositions, segregation of SnO2 phase is observed which is explained by the usage of diffusion flame in the present study. A particle formation mechanism of SnO2/TiO2 composites is proposed based on the single component aerosol formation. Photocatalytic activity of the composite particles is tested for the degradation of methylene blue and is compared with pure TiO2 synthesized under similar conditions. Improved photocatalytic activity of the composite particles is attributed to the stabilized anatase phase and better charge separation due to the coupling of TiO2 and SnO2 within the composite nanoparticles. The adsorption properties of the SnO2/TiO2 particles are similar to the pure TiO2 particles and the PCA can be further improved coupling the advantages of adsorption properties and charge carrier separation in a single system. WO3 is the kind of semiconductor material that has suitable conduction band potential and surface acidity to perform the dual function mentioned above. Due to the non-availability of the suitable volatile precursor for WO3, WO3/TiO2 composite nanoparticles have been synthesized by using flame spray synthesis. W and Ti precursors were dissolved in a suitable solvent and sprayed into the high temperature acetylene flame using an atomizing gas. Particles with controlled W:Ti ratios were produced at various flow rates of precursor solution and the resulting powders were characterized by BET (Brunauer-Emmett-Teller) surface area analysis, XRD, TEM (Transmission electron microscopy), Raman and ATR-IR (Attenuated total reflection infrared) spectroscopy. Two-dimensional coordinatively unsaturated wolframyl species were well dispersed on the TiO2 surface for the samples equal to or less than 3.6 mol% WO3 and contributed to increase the surface acidity. Crystalline WO3 was formed for the samples above 3.6 mol% WO3. The formation of crystalline WO3 is attributed to the enhanced rate of condensation of W species with increasing loading of tungsten. The variation of lambda (defined as the ratio of the actual oxygen-to-fuel ratio of the reactants to the stoichiometric fuel-to-oxygen ratio) affects the type of surface species dispersed on TiO2 particles and thereby the resultant acidity. The improved photocatalytic activity of the composite particles is attributed to the increased surface acidity and better charge separation due to the coupling of WOx species and TiO2 within the composite nanoparticles. The development of a practical photocatalytic system focuses on the cost effectiveness of the process. The usage of the expensive solar concentrators and artificial ultraviolet (UV) irradiation for photocatalytic reactions has negative influences on the cost effectiveness. In addition to the cost effectiveness resulting from using solar energy, abundance of the visible light (55 % compared to 6 % of UV) motivates to synthesize TiO2 nanoparticles that absorb visible light. Nitrogen doped TiO2 nanoparticles that absorbs visible light have been synthesized by hot-wall reactor synthesis. The extent of doping of nitrogen is controlled by varying the hot-wall reactor temperature and the flow rate of the gaseous reactants. Increasing the nitrogen concentration above a certain value reduces the PCA and is attributed to the formation of Ti3+ that act as recombination centre for the charge carriers. The concentration of nitrogen at which significant Ti3+ formation takes place has been systematically investigated by XPS (X-ray photoelectron spectroscopy) measurements.
Book Synopsis Short-term Toxicity of Photocatalytic Titanium Dioxide to Bacteria Under Ambient Conditions by : Ayça Erdem
Download or read book Short-term Toxicity of Photocatalytic Titanium Dioxide to Bacteria Under Ambient Conditions written by Ayça Erdem and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology deals with materials and systems whose structures and components exhibit novel and significantly improved physical, chemical and biological properties, phenomena and processes due to their nanoscale size, which is in the range of 0.1 to 100 nm. Nanotechnology is actively being pursued in many technical fields including aerospace, information science, engineering and medicine, and it represents one of the fastest growing areas of research and development. The nanoparticles have been used in many industrial applications and water/wastewater treatment systems for the last decades. The excessive usage of the nanoparticles has brought a new issue that how the environment has been affected. The earliest toxicological studies showed that the UV light has an adverse effect on the bacteria. As far as the toxicity of fine particles are concerned, TiO 2 is the most studied. This is because TiO 2 has been used as antibacterial agent. However, only the commercial TiO 2 P25, which has an article size of 35 nm, is evaluated. There is no study on the effect of particle size on the toxicity effect of TiO 2 . The early findings of photocatalytic inactivation of bacteria have prompted the attention of many researchers, however, the mechanism of semiconductor catalyzed degradation of bacteria in aqueous media, and properties of the nanoparticles and mechanism controlling nanotoxicity are still unclear. There is a lack of studies on the eco-toxicity of manufactured nanoparticles. What are the fundamental effects of nanoparticles on the growth and survival of bacteria and other microorganisms? What are the synergistic or anti-synergistic effects of nanoparticles? In order to address above questions, the toxicity of nanoparticles to bacteria was studied. The toxicity of different sizes and concentrations of TiO 2 toward bacteria exemplified by E. coli and B. subtilis under dark and different light conditions were discussed. Six endpoints were used to determine the effects of TiO 2 on bacteria: (1) The numbers of viable cells in cell suspensions were determined by plating serially diluted suspensions onto LB-agar plates. (2) Confocal, and scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imaging were facilitated to give a better understanding of the morphological changes happened in the cell structure. (3) Lipid peroxidation of the bacterial cell membrane was measured by measuring the malondialdehyde (MDA) production. (4) Cellular respiration was determined by the reduction of 2,3,5-triphenyltetrazolium chloride (TTC) to its reduced product, 2,3,5-triphenyltetrazolium formazan (TTF). (5) The enzymatic response was measured in terms of the expression of Glutathione S'Transferase (GST). (6) The in vitro response and the quantification of DNA damage was done by ethanol precipitation method explained in standard protocols. The results showed that nanoparticles have adverse effect on the growth of bacteria under both dark and light conditions. The observed bacteria inactivation in dark indicates that undetermined mechanisms additional to photocatalytic reactions were responsible for toxicity. The photocatalytic bacteria inactivation rate was dependent on several parameters such as: physiological state and initial concentration of bacteria, nanoparticle concentration and size, and the intensity of the light source. The die-off of bacteria takes in two stages; fast die-off and slow die-off. The higher particle concentrations and smaller primary particle sizes (16 to 20 nm) appear to be more damaging to the bacteria in absence of light. The bacterial die-off increases as a function of light intensity, whatever the photocatalytic conditions (different TiO 2 concentrations and sizes) were applied. TiO 2 nanoparticles have been shown to exhibit strong cytotoxicity when exposed to UV and solar irradiation. Membrane (lipid peroxidation and respiration) and enzymatic responses, and oxidative DNA damage were detected. In presence of light, higher levels of lipid peroxidation and DNA damage were detected as a function of time and nanoparticle treatment. The lipid peroxidation and the simultaneous losses of both membrane-dependent respiratory activity showed that survival of the bacteria depends on the presence of both light and TiO 2 . Additionally, the microscopy images showed that when bacteria were treated with TiO 2 nanoparticles, the morphology of the cell structure changed. The results from this study highlights the need for caution during the use and disposal of such manufactured nanomaterials to prevent unintended environmental impacts, as well as the importance of further research on the mechanisms and factors that increase toxicity to enhance risk management.
Book Synopsis Application of Titanium Dioxide by : Magdalena Janus
Download or read book Application of Titanium Dioxide written by Magdalena Janus and published by BoD – Books on Demand. This book was released on 2017-07-26 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide is mainly used as a pigment and photocatalyst. It is possible to find it in food, cosmetics, building materials, electric devices, and others. This book contains chapters about application of titanium dioxide in different branches of economy such as the agriculture, the food industry, the medicine, the cosmetics, the water treatment technologies, and the semiconductors.
Book Synopsis Microbial Nanobionics by : Ram Prasad
Download or read book Microbial Nanobionics written by Ram Prasad and published by Springer. This book was released on 2019-06-18 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial Nanobionics: Volume 2, Basic Research Applications continues the important discussion of microbial nanoparticle synthesis with a focus on the mechanistic approach of biosynthesis towards nanobionics. This volume also explores the toxicity of nanomaterials in microbes and their effect on human health and the environment. Special Emphasis is given to the use of polymeric nanomaterials in smart packing for the food industry and agricultural sector. The future of nanomaterials for detection of soil microbes and their interactions and tools for environmental remedies is also comprehensively covered. The rich biodiversity of microbes make them excellent candidates for potential nanoparticle synthesis biofactories. Through a better understanding of the biochemical and molecular mechanisms of the microbial biosynthesis of metal nanoparticles, the rate of synthesis can be better developed and the monodispersity of the product can be enhanced. The characteristics of nanoparticles can be controlled via optimization of important parameters, such as temperature, pH, concentration and pressure, which regulate microbe growth conditions and cellular and enzymatic activities. Large scale microbial synthesis of nanoparticles is a sustainable method due to the non-hazardous, non-toxic and economical nature of these processes. The applications of microbial synthesis of nanoparticles are wide and varied, spanning the industrial, biomedical and environmental fields. Biomedical applications include improved and more targeted antimicrobials, biosensing, imaging and drug delivery. In the environmental fields, nanoparticles are used for bioremediation of diverse contaminants, water treatment, catalysis and production of clean energy. With the expected growth of microbial nanotechnology, this volume will serve as a comprehensive and timely reference.
Book Synopsis TiO2 Photocatalysis by : Akira Fujishima
Download or read book TiO2 Photocatalysis written by Akira Fujishima and published by . This book was released on 1999 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Development and Evaluation of Ag-TiO2 Nano-photocatalysts for the Removal of Natural Organic Matter and Pharmaceuticals by : Azar Fattahi
Download or read book Development and Evaluation of Ag-TiO2 Nano-photocatalysts for the Removal of Natural Organic Matter and Pharmaceuticals written by Azar Fattahi and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasing the population and growing industries lead to contamination of surface and groundwater and threaten the sustainability of aquatic ecosystems and water resources. Some of the main contributors to water pollution include domestic wastes, industrial discharges, and excess use of pharmaceuticals and personal care products as well as pesticides and fertilizers. The incapability of conventional techniques to remove the contaminants has created a need for innovative water treatment solutions, such as advanced oxidation processes (AOPs). AOPs are aqueous phase oxidation methods based on the creation of highly reactive chemical species that mineralize organic pollutants. TiO2 has been widely studied as photocatalysis in AOPs to remove contaminants in water treatment applications. However, the low efficiency under solar irradiation and difficulty in recovering photocatalysis have limited its applications in commercial scale. Doping metals and non-metals to TiO2 structure is a possible mechanism to increase the efficiency and overcome the limitation of using TiO2 in water treatment industries. In the current study, graphene (G) as non-metal and silver (Ag) as a metal dopant were selected to compare the efficiency of photocatalytic reactions of P25 which is the commercial name of TiO2.
Book Synopsis Photocatalysis and Water Purification by : Pierre Pichat
Download or read book Photocatalysis and Water Purification written by Pierre Pichat and published by John Wiley & Sons. This book was released on 2013-03-26 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water is one of the essential resources on our planet. Therefore, fresh water and the recycling of waste-water are very important topics in various areas. Energy-saving green technologies are a demand in this area of research. Photocatalysis comprises a class of reactions which use a catalyst activated by light. These reactions include the decomposition of organic compounds into environmental friendly water and carbon dioxide, leading to interesting properties of surfaces covered with a photocatalyst: they protect e.g. against incrustation of fouling matter, they are self-cleaning, antibacterial and viricidal. Therefore, they are attractive candidates for environmental applications such as water purification and waste-water treatment. This book introduces scientists and engineers to the fundamentals of photocatalysis and enlightens the potentials of photocatalysis to increase water quality. Also, strategies to improve the photocatalytic efficacy are pointed out: synthesis of better photocatalysts, combination of photocatalysis with other technologies, and the proper design of photocatalytic reactors. Implementation of applications and a chapter on design approaches for photocatalytic reactors round off the book. 'Photocatalysis and Water Purification' is part of the series on Materials for Sustainable Energy and Development edited by Prof. G.Q. Max Lu. The series covers advances in materials science and innovation for renewable energy, clean use of fossil energy, and greenhouse gas mitigation and associated environmental technologies.
Book Synopsis Applications of Nanotechnology for Green Synthesis by : Inamuddin
Download or read book Applications of Nanotechnology for Green Synthesis written by Inamuddin and published by Springer Nature. This book was released on 2020-07-02 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traditional methods in synthetic chemistry produce chemical waste and byproducts, yield smaller desired products, and generate toxic chemical substances, but the past two centuries have seen consistent, greener improvements in organic synthesis and transformations. These improvements have contributed to substance handling efficiency by using green-engineered forerunners like sustainable techniques, green processes, eco-friendly catalysis, and have minimized energy consumption, reduced potential waste, improved desired product yields, and avoided toxic organic precursors or solvents in organic synthesis. Green synthesis has the potential to have a major ecological and monetary impact on modern pharmaceutical R&D and organic chemistry fields. This book presents a broad scope of green techniques for medicinal, analytical, environmental, and organic chemistry applications. It presents an accessible overview of new innovations in the field, dissecting the highlights and green chemistry attributes of approaches to green synthesis, and provides cases to exhibit applications to pharmaceutical and organic chemistry. Although daily chemical processes are a major part of the sustainable development of pharmaceuticals and industrial products, the resulting environmental pollution of these processes is of worldwide concern. This edition discusses green chemistry techniques and sustainable processes involved in synthetic organic chemistry, natural products, drug syntheses, as well various useful industrial applications.
Book Synopsis Development of Highly Active Supported TiO2 Photocatalyst for Waste Water Purification by : Nor Hafizah binti Ahmad Tarmizi
Download or read book Development of Highly Active Supported TiO2 Photocatalyst for Waste Water Purification written by Nor Hafizah binti Ahmad Tarmizi and published by . This book was released on 2010 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground water pollution has become one of the major concerns to the government due to the rapid development of the industries such as pharmaceutical and petrochemical. An excessive amount of polluted water release from these industries can cause negative impact to the public when the water is consumed. Utilization of membrane filtration, chloride dioxide, and activated carbon are among conventional methods to treat the polluted water to date. Today, TiO2 photocatalyst is recognized as a potential material for water treatment as it is non-toxic and requires solar energy to initiate its redox mechanism to degrade organic and inorganic pollutants. Nonetheless, separation of TiO2 powder from the purified water after the treatment can be very tedious thus secondary operation is needed to separate them. In this research, TiO2 photocatalyst powders with nanosize particles were synthesized via sol-gel method. The mol ratios of water-to-TPT were varied at 0.5 (Powder 0.5), 1 (Powder 1), 2 (Powder 2), 3 (Powder 3), 4 (Powder 4), and 5 (Powder 5). Then, the gel TiO2 powders were dried at 200 °C for one hour followed by calcination at 400 °C. The obtained powders were then immobilized with cement for phenol degradation. FESEM surface morphologies of TiO2 powders showed that the powders had spherical shape at lower ratios of water-to-TPT and lost its ability to form homogeneous spherical shape as the ratios became higher. XRD analysis proved the obtained TiO2 powders were pure anatase and fully crystalline after being calcined at 400 °C. The TG/DTA results revealed the crystallization temperature of smaller powder particle was higher as it needed more heat to change its phase than bigger powder particles. The cement-bonded TiO2 photocatalysts were found to be well-adhered to the cement surface when analyzed with FESEM. Photocatalytic performance of cement-bonded TiO2 photocatalysts of Powder 1, 2, and 5 were evaluated from their photodegradation activity with phenol solution as the representative organic pollutant. Langmuir-Hinshelwood (L-H) model was employed to compare their photoefficiency. Powder 1 has higher value of adsorption equilibrium constant due to its smaller particles that capable of adsorbing more phenol molecules to be degraded. Meanwhile, Powder 2 has better reaction rate constant as its high crystallinity has provided efficient charge separation to induce the redox mechanism in degrading phenol molecules.
Book Synopsis Synthesis, Characterization and Photocatalytic Application of TiO2 Nanosized Particles by : Dongliang Liao
Download or read book Synthesis, Characterization and Photocatalytic Application of TiO2 Nanosized Particles written by Dongliang Liao and published by . This book was released on 2007 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In this thesis, effects of surfactant composition and concentration on shape, size, zeta potential, and photocatalytic activity of TiO2 nanosized particles are reported. Spherical, cubic, rod, ellipse and leaf-like shaped TiO2 nanosized particles were obtained with the addition of different surfactants in various composition and concentrations during preparation. The results show that the shape and size of the TiO 2 nanosized particles depend on not only surfactant composition but also surfactant concentration. The pH dependence of zeta potential of TiO2 nanosized particles was studied. A unique finding is that TiO2 nanosized particles shaped by sodium dodecyl sulfate (SDS) have two isoelectric points (IEPs), while other shape-controlled TiO2 nanosized particles have only one IEP. At neutral pH, shape-and size-controlled TiO2 nanosized particles have a more negative zeta potential than TiO2 nanosized particles obtained without the addition of surfactants during synthesis and commercial anatase TiO2 nanosized particles Degussa P-25. Different zeta potential values are observed for TiO2 nanosized particles obtained with the addition of different surfactants during preparation.
