Beginning intro: Research and advancement of TiO2 nanowires have increased tremendously due to recent findings about its unique chemical and physical properties. Many new methods of synthesizing TiO2 nanowires have been created and improved. Specifically, three growth methods are reviewed in this survey: (1) sol-gel method (2) direct oxidation method (3) hydrothermal method. Three applications of TiO2 nanowires are touched in this survey: (1) photocatalytic (2) gas sensing (3) dye-sensitized solar cell.
Introduction
Titanium dioxide (TiO2) is often found in commercial products such as paint, sunscreen, toothpaste, and etc. [7]. Further research and advancement of TiO2 was initiated after the discovery of its photocatalytic property that allows it to split water on TiO2 electrodes in 1972 [7]. TiO2 nanosized particles can be synthesized in various shapes such as nanotube, nanorod, nanobelt, and etc. [N&N]. Specifically, this section is the focus on the growth mechanism, characterization, and applications of TiO2 nanowires.
Inorganic nanowires often exhibit unique property that is useful for future applications. As the sizes of materials are decreasing down to the nanoscale level, the physical structure and chemical properties of nanomaterials are also diverging away from its bulk form [N&N]. Nanowires display the quantum confinement effect which describes the energy level of electrons as discrete unit [N&N]. For example, the transfer of electrons from the valence band to the conducting band requires a specific amount of energy [N&N]. Additionally, the surface area to volume ratio increases as the particles gets smaller [N&N]. This property supports many of the future application of TiO2 nanowires that requires a large surface a...
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The microscope is an advancement in technology in Chemistry since it was invented since 1959. The technology that involves Chemistry has evolved as the Chemistry that involves technology. From looking at cells 500 times greater to the naked human eye, and from looking at cells to bacteria in an animal to what goes on in a plant and how it absorbs light, the microscope can change the world in just a second when a new discovery is made. People has come very close to discovering a cure from cancer but all the times it has failed time and time again A cure for someone who needs a cure for cancer can happen in a moment with the help of the microscope and the necessary resources. Once people look at life through a microscope, there is no stopping or telling on how many discoveries and cures we can find.
In basic research, special model systems are needed for quantitative investigations of the relevant and fundamental processes in thin film materials science. In particular, these model systems enable the investigation of i.e. nucleation and growth processes, solid state reactions, the thermal and mechanical stability of thin film systems and phase boundaries. Results of combined experimental and theoretical investigations are a prerequisite for the development of new thin film systems and tailoring of their microstructure and performance.
By using strong oxidizing agent, oxygenated functionalities are introduced in the graphite structure which not only expand the layer separation, but also makes the material hydrophilic. Hydrophilic mean that they can be dispersed in water. This properties has enable graphite oxide to be exfoliated in water by using sonification, ultimately producing single and few layer of graphene that has been known as graphene oxide. The properties of graphene oxide is its easy dispersability in water and other organic solvents, as well as in the different matrixes due to the presence of the oxygen functionality (Jesus de La Fuente., 2011).
Graphene has received great mass media coverage since Geim and Novoselov published their foundlings about monocrystalline graphitic films in 2004, which won them the Nobel Prize in Physics in 2010. (Novoselov et al, 2004) It has been described as the wonder substance or super material by the mass media, not only because it is the thinnest material ever known and the strongest ever measured, but also due to its excellent electrical, thermal, mechanical, electronic, and optical properties. It has high specific surface area, high chemical stability, high optical transmittance, high elasticity, high porosity, tunable band gap, and ease of chemical functionalization which helps in tuning its properties (Geim et al, 2007) Moreover, graphene has a multitude of amazing properties such as half-integer room-temperature quantum Hall effect (Novoselov et al, 2007), long-range ballistic transport with almost ten times greater electron mobility than that of silicon, and availability of charge carriers that behave as massless relativistic quasi particle, known as Dirac fermions. (Geim et al, 2007) The outstanding electrical conductivity and the transparency and flexibility of graphene-based material have led to research and development of some future technologies, such as flexible and wearable electronics. In addition, graphene can also be used for efficient energy storage materials, polymer composites, and transparent electrodes. (Geim et al, 2007) This paper presents a
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Although Solar Energy is a flexible source of where energy could be directly or indirectly converted into forms of energy, it’s still not perfect. With its inefficiency, scientists are trying to find alternative solution to store solar cells for as long as possible. The main process of capturing solar energy happens at the nanoscale. With solar cells, it gets more efficient the tinier it gets. The converting rate of solar energy is equally price competitive as fossil fuel, with a dollar per watt of solar energy. With the help of nanotechnology, it could help raise solar energy conversion efficiency and help lower costs making it the ultimate method of raw energy conversion. To make sure the process of generating energy is kept at a low cost and energy output...
Because of its diverse properties, both chemical and physical, zinc oxide is widely used in numerous areas. Among the various potential applications of ZnO that are applicable in today’s industries ranging from rubber to pharmaceutical, from textiles to agriculture, and from electronics and electrotechnology industries. The use of zinc oxide is not limited to only a certain region or area, but rather it is use
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Design , characterization, production and application of materials devices and systems by controlling shape and size of the nanoscale.
Grundmann, Marius. Physics of Semiconductors: An Introduction Including Devices and Nanophysics. New York: Springer, 2006. Print.
The electron microscope can magnify objects that are as small as the length of an atom to one million times larger. They are usually used to examine cells and molecules. This is done by increasing the electron’s penetration in a vacuum until their wavelength is exceedingly fast. When this happens, rays of light from the electrons are focused on the cell on the stage, creating a duplicate projection on an electron- sensitive plate.