Search query: Synthesis of rutile titanium

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abstract: The synthesis, structure, and electrical performances of titanium dioxide (TiO 2 and also doped TiO 2 thin films, a capacitor dielectric for dynamic random access memory (DRAM) and a resistance switching material in resistance switching RAM (ReRAM) are reviewed. The three dimensionality of these structures and the extremely small feature sizes 2 based layers to exhibit high degree of conformality. Atomic layer deposition is, therefore, the method of choice in respect of film growth for these applications. The unique arrangement of the TiO 6 octahedra in the rutile structure, which results in the value for dielectric constant of the dielectric layer, e r >100) makes the material especially attractive as the capacitor dielectric layer in DRAM. Removing some of the oxygen ions from the rutile structure and arranging the resulting oxygen vacancies on a specific crystallographic plane results in the so called Magneli phase materials, which show distinctive conducting semiconductor or metallic characteristics. External electrical stimuli can cause the repeated formation and rupture of conducting channels that consist of these Magneli phase materials in the insulating TiO 2 matrix, and this aspect makes the material a very feasible choice for applications in ReRAM. This article reviews the material properties, fabrication process, integration issues, and prospect of TiO 2 films for these applications.
author_names: Seong Keun Kim

Kyung Min Kim

Doo Seok Jeong

Woojin Jeon

Kyung Jean Yoon

Cheol Seong Hwang
title: Titanium dioxide thin films for next generation memory devices
year: 2013

abstract: Recent referential studies on the preparation of titanium tetrachloride and titania nanoparticles were briefly reviewed. Three important processes, namely, the pretreatment of ore, the chlorination of rutile ore and the transformation of titanium tetrachloride were analyzed using thermodynamic and particle dynamic theories. The optimal reaction conditions (temperature, etc. for the three processes were obtained. Effects of additives or contaminates in the chlorination and oxidation processes on producing titania were analyzed. Strategies to control titania nanoparticle size were found.
author_names: Hong Ruo

M Teshneh Lab
title: Numerical investigation for the synthesis of titania nanoparticles from Ore to Oxide
year: 2005

abstract: Titanium dioxide (TiO2) nanoparticles (NPs) have a wide range of applications in industry and medicine. TiO2 NPs have unique optical, electronic, photocatalytic and antimicrobial properties [1] which can be exploited towards novel drug delivery systems and also for water purification [2] dye sensitized solar cells, photonics and food preservation [3] Three main phases of TiO2 are anatase, brookite and rutile [4] Synthesis of TiO2 NPs with controlled particle size can be reached using energy consuming, sophisticated, conventional chemical and physical synthesis methods. However, this approach has intrinsic drawbacks due to high cost and risk to the environment. Comparatively, eco friendly, costeffective and non toxic NP synthesis techniques using microorganisms and plant sources are in demand [5] This green synthesis has the ability to produce higher yields of NPs under mild laboratory conditions facilitating largescale production. Microbial TiO2 NP synthesis has been reported using several microorganisms including Bacillus cereus [6] Fusarium oxysporum [7] B. subtilis [8, 9] Aspergillus species [10, 11] B. mycoides [12] and Lactobacilli [13] Since these are renewable sources, it is environmentally less harmful and generates less amount of toxic waste. TiO2 NP biosynthesis is thought to arise as a result of the reduction of the metal salts to nanosized metal particles mediated by the enzymatic and chemical interactions. Jha et al. [14] suggested that the negative electro kinetic potential of microbes can attract cations triggering the series of events leading to biosynthesis of NPs. The presence of reducing agents such as glucose reduces the redox potential thereby enhancing NP formation. TiO2 NPs have good antimicrobial potential, where they deactivate cellular enzymes and DNA and also form pores in bacterial membranes leading to fluid loss and cell Received: July 9, 2018 Revised: August 14, 2018 Accepted: August 20, 2018
author_names: Mmk Peiris

Tdcp Guansekera

P M Jayaweera

S S N Fernando
title: jmbReview TiO 2 Nanoparticles from Baker s Yeast A Potent Antimicrobial
year: 2018

abstract: In this paper, synthesis method of acrylated urethane based on polyethylene glycol and toluene di isocyanate as a mixture of two isomers (2,4 and 2,6) has been investigated by application of IR spectra and GPC technique In this method, reaction schemes were controlled by surveying the NCOand OH absorption peak elimination and NHabsorption peak formation in IR spectra during the reaction. The mixture of the two isomers leads acrylated urethane resins to contain three oligomers (II, 111 and IV) in the final product. The study of physical and mechanical properties of y cured resin showed that hardness and impact resistance vary with increase in dose meanwhile these quantities indicate a little variation after 60 kGy This could be due to increasing of cross link density. Also, addition of reactive monomers to the resin showed that increase in double bonds density in the resin system at a given dose, caused an increase in hardness and a decrease in impact resistance By addition of a rutile type titanium dioxide as pigment, the hardness of film increases, but the variation of hardness dose curve in both unpigmented and pigmented film is the same.
author_names: A Shojaee

Faramarz Afshar Taromi

F Khouylou
title: SYNTHESIS AND PROPERTIES OF G(CO 60) CURED ACRYLATED URETHANE COATING
year: 2000

abstract: Titanium, which has been reported to be less dense than steel but stronger than it, is a light, strong, silvery and corrosion resistance metal which exist as the ninth most abundant element in the earth's crust, and can be found in nature in the form of various oxides, of which the most common is titanium dioxide (TiO2) [1 2] Titanium dioxide, which is also referred to as TiO2 or titania is a thermally stable, noninflammable and poorly soluble white solid inorganic substance which can be regarded as a global product due to its wide range of applications. It was first introduced as a commercial product in 1923, and has been used for many years in a vast range of consumers and industrial goods including paints, catalyst systems, medical devices, aerospace and turbines, ceramics, adhesives, sunscreens, ointment, toothpaste, coatings, paper and paper board, coated fabrics and textiles, plastics and rubber, printing inks, cosmetics and pharmaceuticals, food colorants, water treatment agents, floor coverings, roofing materials and in automotive products [2] TiO2 is a vital research material due to its biocompatibility, physical optical and electrical properties as well as the stability of its chemical structure, and can exist in the crystalline forms of brookite, rutile and anatase. The common forms are anatase and rutile which has density and band gap of 3.9 g/ml, 3.2eV (corresponding to a UV wavelength absorption of 385nm) and 4.26 g/ml, 3.0 eV (with excitation wavelengths that extend into the visible light range of 410 nm) respectively. However, anatase which is considered as the most preferred and photochemical active phase of TiO2 is the most stable form by 8 12 KJ mol and can be converted to rutile by heating to a temperature of 700 oC, while brookite which is the third crystalline form of TiO2 is uncommon and unstable [3 6] Due to the impressive and advantageous properties of TiO2 nanoparticles (NPs) it has receive a wide attention in many fields such as tackling of energy and environmental challenges, improvement in health care, biomedical devices and drug delivery systems [7] In this review, the physical, chemical and biological synthetic methods for the preparation of TiO2 NPs have been explained. The modifications, applications and challenges of TiO2 NPs were also discussed respectively. ABSTRACT
title: Synthesis, Modification, Applications and Challenges of Titanium Dioxide Nanoparticles
year: 2019

abstract: In solid phase processing, microwaves are beginning to be applied for sintering and synthesis of ceramics1)~7) heating and sintering of metal powders8)~12) synthesis of glasses13),14) and so on. Especially, in high temperature region such as ceramic synthesis process, rapid synthesis, sintering, and energy saving process is required, and are being developed utilizing the feature of microwave processing such as internal heating, volumetric heating etc. which is independent of the heat conduction law15),16) In the synthesis of materials that do not absorb microwaves, we can utilize a heat source material called a susceptor around the container17) and get the benefit of microwave rapid heating. In addition, using a single mode cavity, which can confining the electromagnetic field in the cavity, we can heat materials with higher efficiency than the multi mode microwave heating furnace such as microwave oven. Single mode cavity can separate the position of maximum intensity of electric field and magnetic field, and it is also used for research on the principle of microwave processing focusing on the effects of microwave electromagnetic field18),19) By devising the sample setting and microwave apparatus as described above, it is possible to synthesize almost all functional materials that can be synthesized in an electric furnace within a short period of synthesis time5) On the other hand, there are few cases of synthesis of transition metal oxide nano particles, which are difficult to produce in an electric furnace. The most problem to synthesize nanoparticles is sintering and coarsening of the sample at high temperature, which needs for solid state processing. However, by taking advantage of the microwave process such as rapid heating and internal heating, it is possible to overcome this problem. In the review, we show that reduced titanium oxide (Ti4O7) nanoparticles and aluminum nitride (AlN) nanoparticles are synthesized at low temperature and short time by rapid carbothermal reduction process using microwaves. The key strength of this method is retaining the morphology of oxide nanoparticles as a pristine material. Rutile (TiO2) and alumina (Al2O3) nanoparticles as pristine materials are being applied to cosmetics, electronic components, and so on in Japan, and they are produced industrially (several hundred tons) respectively. Rutile and alumina nanoparticles are also possible to control these particle size according to the application, which is very advantageous for use as a pristine material. On the other hand, these oxides 88 Journal of the Japan Petroleum Institute, 61, (2) 88 97 (2018)
author_names: Jun Fukushima

Hirotsugu Takizawa
title: Microwave Synthesis of Ti4O7 or AlN Nanoparticles by Rapid Carbothermal Reduction Process
year: 2018

abstract: As the adoption of components fabricated via titanium powder metallurgy (PM) techniques becomes more prevalent, and projected to increase at a substantial rate over the next decade, especially in the field of additive manufacturing (AM) there is a necessity to increase titanium powder production capacity from the current annual level of ca. 6000 tonnes per annum. At present a well documented barrier restricting this widespread implementation, is the inherently high cost of the feedstock, an issue which to date has been neglected to some degree, at the expense of developing the individual powder metallurgy routes. The scope of this overview therefore is to provide an insight of both established and novel methods of titanium powder production, as potential opportunities to satisfy this growing demand. Particular emphasis will focus on Metalysis, a company founded to commercialize an innovative electrochemical approach for the synthesis of metals and alloys from their respective oxides, where the ability to generate titanium eloquently demonstrates the extent of its capabilities.The patented Metalysis technology, exploiting the FFC(r) Cambridge process, lends itself to producing alloys and intermetallics, where Ti 6Al 4V provides a prime example of this. Furthermore, as electrolysis occurs solely in the solid state, issues pertaining to segregation due to dissimilar densities and melting points are avoided. It is possible to tailor both the average particle diameter and size distribution of the product targeted powder metallurgy (PM) applications, based upon appropriate selection of the feed. The attraction of this strategy is that the steps associated with conventional metal powder synthesis are circumvented, resulting in a significant cost reduction. Moreover it has recently been revealed that titanium can be produced directly from naturally occurring ore (beach sand) and synthetic rutile, with the ensuing product presenting itself as an inexpensive and abundant feedstock for additive manufacturing (AM) This represents a paradigm shift in the availability of consumables for the 3D printing market.
author_names: Ian M Mellor

G R Doughty
title: Novel and Emerging Routes for Titanium Powder Production An Overview
year: 2016

abstract: Abstract Black titanium dioxide (TiO2) has been one of the most researched photocatalyst in recent years. Its ability to overcome the limitations of pristine TiO2 through enhanced visible light absorption and reduced recombination of photogenerated charge carriers have gathered the attention of the scientific community since its discovery in 2011. Numerous synthesis routes have been developed for black TiO2 owing to its superior activity as compared to pristine white TiO2 in various applications. Extensive studies have enabled understanding its superior activities and most studies reveal that defect species like Ti3+ and oxygen vacancies are responsible for the enhanced photoactivity. However, closer look reveals that mere presence of defects does not necessarily lead to improved performance of black samples. Studies show that the same defect species can have negative impact on its performance. In fact, different factors like defect concentration, defect location, valence band and conduction band levels, synthesis route, synthesis conditions, anatase/rutile ratio etc. play a key role in the working mechanisms of black TiO2 samples. In some cases, black TiO2 samples have actually shown reduced photoactivity as compared to the pristine ones. Such results have led to some conflicting ideas related to role of defects in overall photoactivity, photoactivity under visible spectrum, existence/co existence of Ti3+ species and oxygen vacancies and their location, connection between band gap values and photocatalytic activity etc. The intricacies of black TiO2 are yet to be thoroughly understood as evidently seen in the differing properties reported in many studies. This review summarizes the significant properties of black TiO2 and identifies some of the conflicting points observed in literature where further light needs to be shed for better understanding.
author_names: Thangarasu Rajaraman

Sachin P Parikh

Vimal G Gandhi
title: Black TiO2: A review of its properties and conflicting trends
year: 2020

abstract: Titanium dioxide is an important metal oxide semiconductor (MOSs) used in many electronic applications, the most famous of which are gas sensor applications. This review discusses the techniques used for preparing the TiO2 thin films and the effect of the crystalline phases in which this compound forms, on the gas sensing properties. There are three phases to crystallize titanium dioxides, brookite, anatase, and rutile phase. Amongst these varied phases of crystal, the greatest steady main phase is rutile. The phase of anatase and brookite are usually more stable than the rutile phase as the surface energy of them is less than that of the rutile. Therefore, the applications of sensing by anatase TiO2 and rutile TiO2 were fully studied. TiO2 characterizations were established on surface reactions using oxidizing or reducing gases, which; therefore, influences the conductivity of the film. Titanium dioxide gas sensors have healthier steadiness and sensitivity at high temperature compared with that of the other metal oxides. Surveys on titanium dioxide thin film applied in gas sensor devices used in a varied range of applications such as sensor devices, dye sensitized solar cells, and catalysis. The gas sensor is a function of the crystal structure, particle size, morphology, and the method of synthesis. In this work, characteristic of the titanium dioxide films investigated using various techniques, as reported by many researchers. The aim of this study was to review previous studies through which the best properties can obtained to manufacture TiO2 gas sensor thin films with high sensitivity.
author_names: Jamal M Rzaij

Amina M Abass
title: Review on: TiO2 Thin Film as a Metal Oxide Gas Sensor
year: 2020

abstract: Advancement of the nanotechnology variation in the synthesis method plays an important role for technological revolution. The different branches of science is depends on the crystal structure of the molecules. The variation in chemical and physical structure of the nanoparticles using hydrothermal technology was discussed. Different types of nanomaterials were also discussed using this methodology. Keywords; Hydrothermal method, supercritical temperature, zirchonium oxide, titanium oxide Introduction The nucleation and the growth of the nanoparticles plays an important for various applications. The size, shape and the crystal structure effects the nucleation of the nanoparticles.Due to the wide range applications and the large surface to volume ratio the role of nanoparticles are also important for the industrial purpose as well as household. Most of the nanoparticles are better than bulk materials due to their confine size, surface area, porosity and the better mechanical properties. The nano sized particles also shows tremendously catalytic application in organic synthesis. These particles are better than bulk particles because nanoparticles are easily dispersed without any agglomeration[1] Nanoparticles are widely used in different areas such as electro chemical sensors, gas sensors, solar cells, photovoltaic cells, and photocatalysis. Now a days the medical field are also dependent on nanoparticles for drug delivery, hypothermia, bio sensing, nano medicine and many more. The various methods are adopted for the synthesis of nanoparticles suchas laser ablation, sono chemical, chemical vapour deposition, sol gel and hydrothermal.Out of them hydrothermal method is the best method to synthesize the nanoparticles.In this method only water used as a solvent and only heat is required,no calcination are required. Other benefits of this method is the proper orientation of crystals and their growth at a high temperature and pressure is required. Generally for the hydrothermal reaction the temperature is below 300degC and the pressure is less than 25 MPa is required. Because the critical temperature of the water is 374degC and the pressure is 22 MPa. The hydrothermal reaction depends on the various factors such as solubility, solvent antisolvent interaction and the dielectric constant. When the inorganic salt dissolved in the water the dielectric constant of the water reduced eight times under supercritical situtations and the rate of the reaction enhanced two to three folds. The phenomena behind this theory is electrostatic theory. On the basis of this phenomena the growth and the nucleation of the nanoparticles are effected and also alters the crystal structure of the nanoparticles[2] The requirement of the industry is the fine crystal structure, easily transformation, and the phase equilibrium of the reaction. In hydrothermal reaction if we altered the temperature and pressure conditions the morphology (c) 2019 JETIR January 2019, Volume 6, Issue 1 www.jetir.org (ISSN 2349 5162) JETIRDY06111 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 701 and the structure of the nanoparticles was changed[3] In the present article we reported the various nanoparticles are synthesized by hydrothermal method and their role in different applications. The morphology of these nanoparticles are also reported. Various nanoparticles formed by hydrothermal method Magenese oxide nanoparticles The different state of MnO2 nanoparticles are used in supercapacitor, lithium ion, and solar cell applications. The different morphology of the MnO2 nanoparticles are depends on the precursor used during the reaction[4] The surfactant free different shape of MnO2 nanoparticles was synthesized by Chen et al. in the presence of water and isopropanol. When the reaction was carried out in the presence of isopropanol at its refux point the needle shaped MnO2 nanoparticles was obtained while when this reaction was carried out in the presence of ammonium persuphate which act as an oxidizing agent in the reaction the single crystal nanowires of MnO2 was achieved[5] Simiarly When this reaction was carried out in the presence of NaOH solution at 170degC for 12 hr in the Teflon coated seal tube the bundles of MnO2 nanoparticles was obtained. This process is reported by Ma et al. [6] Zirchonium oxide ZrO2 nanoparticles are widely used in optical, mechanical and electrical applications. The bans gap of the ZrO2 nanoparticles is wide band gap that's by it used in photocatalytic applications. This nanoparticles are synthesized by different methods such as sol gel, laser ablation, sonochemical and green method. But the hydrothermal method is the most advanced method to synthesize the various morphological nanoparticles of zirchonium oxide. Because in this method the ultrafine nanoparticles was obtained due to low agglomeration, homogenous distribution, control morphology and size distribution. L.Kumari et al. have synthesized ZrO2 nanoparticles using the zirchonim nitrate precursor less than 200 degC for 24 hr in Teflon coated seal tube. During the variation of the reaction time the morphology of the nanoparticles are also varied from hexagon to rod like nanoparticles [7] Titanium oxide nanoparticles TiO2 nanoparticles used in various areas such as photocatalysis, sensors, medicine and many more. The specific crystal structure is required for each type of application. Because titanium oxide nanoparticles possess two types of crystal structure such as anatase and rutile. For the catalysis applications high temperature is required and for that anatase crystal structure is required for the titanium oxide nanoparticles while for high permetivity and resistence the rutile form of the titanium oxide nanoparticles are required. The varsity of the titanium oxide nanoparticles in different applications, many methods are required for the synthesis, but for the specific crystal structure and the morphology hydrothermal and microwave method is the best method to synthesizethis nanoparticles. Focher et al. have been synthesized titanium oxide nanoparticles (c) 2019 JETIR January 2019, Volume 6, Issue 1 www.jetir.org (ISSN 2349 5162) JETIRDY06111 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 702 using TiOCl2 precursor for 30 min to 1 hr under hydrothermal conditions. The obatained nanoparticles are hexagonal shape[8]
author_names: Deepak Kumar
title: Hydrothermal Methods Of Nanoparticles: An Overview
year: 2020