CHEMICAL VAPOR TRANSPORT Meaning and
Definition
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Chemical vapor transport refers to a process in which chemicals are transported from one location to another through the use of a gas or vapor phase. It typically involves the movement of solid or liquid substances in gaseous form, which are carried by a suitable transport gas. This method utilizes the principles of diffusion and thermodynamics to facilitate the transport of chemicals.
In chemical vapor transport, a solid or liquid compound to be transported is mixed with a carrier gas that has the ability to interact with the compound. The carrier gas is chosen based on factors such as its chemical inertness, high diffusivity, and compatibility with the substance being transported. The mixture of the compound and the carrier gas is then heated, usually in a sealed container or tube, where the compound vaporizes and becomes dispersed in the gas phase. The vapor then diffuses within the system due to concentration gradients until it reaches a cooler region where it condenses or reacts with a suitable substrate. This results in the deposition of the compound at the desired location.
Chemical vapor transport is widely used in various scientific and industrial applications. It is commonly employed in the synthesis of thin films, crystals, and nanomaterials, where precise control over the chemical composition and morphology is required. The process allows for the transportation of volatile compounds or compounds with low melting points, enabling their delivery to specific locations within a controlled environment. Chemical vapor transport also offers the advantage of producing highly pure materials, as impurities are typically left behind in the source material during the transport process.
