Advanced Cold Plasma Synthesis of Organic Networks and Molecules

当对气体施加足够高的电势，导致其部分电离时，就会产生冷的非平衡等离子体。相关的电场将能量传递给自由电子，产生“热”高能电子，而不受影响的中性分子（构成气体的大部分）保持接近环境的平均温度。这种独特的环境允许触发具有高活化能的化学反应，这在室温下通常是无法实现的，没有高温的相关影响，如熔化和碳化。冷等离子体已经在关键技术领域找到了应用，主要是照明（荧光灯管）和微电子，它们被用于沉积和蚀刻构成电子芯片的材料层。冷等离子体的另一个重要应用领域是表面工程，冷等离子体被用来改变材料的表面特性，使其适合特定的应用。一种常见的应用是在印刷前使用常压电晕放电来改善聚合物薄膜的润湿性，以使油墨能够正确地粘附在塑料上。另一个应用，在附加价值谱的另一端，是生物医学植入物的表面工程，有利于它们在体内的结合。近年来，冷等离子体与液体之间的直接相互作用已成为一个新的和迅速扩大的研究领域，用于破坏或合成分子以及直接的医疗应用。

Cold, non-equilibrium plasmas are created when a sufficiently high electrical potential is applied to a gas, causing its partial ionization. The associated electrical field transfer energy to the freed electrons, generating “hot” energetic electrons while the unaffected neutral molecules, which constitute the majority of the gas, maintain an average temperature close to ambient. This unique environment allows to trigger chemical reactions having high activation energies, which are generally unachievable around room temperature, without the associated effects of high temperatures, such as melting and carbonization. Cold plasmas have found applications in key technological areas, the main ones being lighting (fluorescent tubes) and microelectronics where they are used for deposition and etching of material layers that constitute electronic chips. Another key field where cold plasmas have found important applications is surface engineering where cold plasmas are used to alter to surface properties of materials to render them suitable for given applications. A common application is to use an atmospheric pressure corona discharge to improve the wetting of polymer films before printing in order to allow inks to adhere properly to the plastic. Another application, at the other end of the added value spectrum, is the surface engineering of biomedical implants to favour their incorporation in the body. Recently, direct interactions between cold plasma and liquids for destruction or synthesis of molecules as well as for direct medical applications has been a new and rapidly expanding research area. This proposal presents a research program aimed at developing cold plasma methods for the synthesis of organic molecules and networks macromolecules with a mainly random structure - both as thin films, from the gas phase, and directly in liquids. The proposed program presents a comprehensive approach with developments in reactor and source design, characterization methods, fundamental studies and application oriented developments. A significant portion of the program is dedicated to surface engineering involving the deposition of thin organic coatings prepared by plasma enhanced chemical vapour deposition of mixtures of small organic molecules. This approach has been shown highly successful to produce tailored solutions, in the form of pH responsive functional coatings with adjustable surface chemistry and surface charge, to various industrially relevant problems going from absorption of CO2 to controlling the speed of liquid flow in microfluidic devices. The impact of the work described here will be felt on a wider range of applications, going from medical implants, to cell culture material and in the polymer processing industry.