Establishment of novel materials surface treatment/modification technology with using supercritical fluid plasma beam

(1)超临界流体介质阻挡放电微等离子体处理装置研制研制了一种超临界流体介质阻挡放电（DBD）微等离子体处理装置。利用该装置，我们将光学发射光谱（OES）应用于高压CO_2环境下直至超临界条件下产生的等离子体。采用介质阻挡放电（DBD）和直流放电两种等离子体。在超临界条件下，C_2分子和O原子在两种放电方式下的光谱都很明显。在2.0 MPa下，DBD中C_2的旋转温度约为4000 K。(2)超临界流体等离子体在新型材料表面处理与制造中的应用我们已经将电弧型和DBD型两种超临界流体等离子体应用于材料表面处理与制造。它们对工艺参数（如温度、压力和频率）对合成材料的依赖性已经得到了深入的研究。通过这些实验，我们成功地在400K左右以scCO_2为原料合成了碳纳米管和碳纳米洋葱等碳纳米结构材料及其薄膜。此外，在400K左右也成功沉积了金属膜。(3)激光诱导超临界流体等离子体的产生成功地实现了激光诱导超临界流体等离子体（scCO_2和scH_2O）的产生。此外，还观察到受激拉曼散射现象。

(1)Development of a Supercritical Fluid Dielectric Barrier Discharge Microplasma Processing DeviceWe have developed a supercritical fluid dielectric barrier discharge (DBD) microplasma processing device. Using this device, we applied optical emission spectroscopy (OES) to plasmas generated in high-pressure CO_2 environments up to supercritical condition. Two types of plasmas, namely, dielectric barrier discharge (DBD) and DC discharge were employed. Up to supercritical conditions, the spectra of C_2 molecule and atomic O were remarkable by optical emission spectroscopy of both types of discharge. Rotational temperature of C_2 was estimated as approximately 4000 K in DBD at 2.0 MPa.(2)Application of supercritical fluid plasmas to novel materials surface treatment & fabricationWe have applied two types of supercritical fluid plasmas, namely arc type & DBD type, to materials surface treatment and fabrication. Their dependences of process parameters, such as temperature, pressure, and frequency, on synthesized materials have been intensively investigated. Through these experiments, we have succeeded in carbon nanostructured materials, such as carbon nanotube and carbon nano-onion, synthesis and their thin films from scCO_2 as raw-materials at around 400K. In addition, metal film deposition has been also succeeded at around 400K.(3)Generation of Laser-induced supercritical fluid plasmaThe generation of laser-induced supercritical fluid plasma (for scCO_2 and scH_2O) has been successfully achieved. Moreover, SRS(Stimulated Raman Scattering) phenonema has been observed.