碳纳米管工具电极的制备

Preparation of Carbon Nanotube Tool Electrode

纳米工具电极是进行纳米电解加工的必备条件,其特征尺寸直接影响纳米结构的最终尺寸.提出了利用电弧放电将碳纳米管束焊接在钨针尖上的纳米工具电极制备方法,并通过试验研究了钨针的针尖圆弧半径和放电电压对制备碳纳米管工具电极的影响.试验结果表明,不同尖端圆弧半径的钨针,所需有效放电电压不同,圆弧半径越小,有效放电电压越小,强电场分布越集中,越容易将碳纳米管束焊接在针尖的顶端;圆弧半径越大,强电场分布区域越大,越不容易控制碳纳米管束焊接的方向性.在针尖圆弧半径约为100 nm和300 nm的钨针上,放电电压分别为25 V和35 V时,成功制备出碳纳米管工具电极.

Electrodes of nanometer scales, which can directly determine the dimension of structure, are essential for electrochemical nano-machining. Welding carbon nanotube（CNT） bundle on the tip of tung- sten needles by voltage arc discharge was introduced to prepare nanometer tool electrodes. And the influ- ences of tungsten needle tip arc radius and discharge voltage on CNT tool electrode preparation were ex- perimentally investigated. Experimental results indicate that tungsten needles of different tip arc radiuses need different effective discharge voltages, and that the smaller the tip arc radius is, the smaller the weld- ing voltage will be. It is easier for CNT bundle to be welded on the smaller tip arc radius of tungsten nee- dle as the electric field is more concentrated, while it is more difficuh to control the welding direction as the electric field distribution area of bigger tip arc radius is wider. At the discharge voltage of 25 V and 35 V, CNT tool electrodes can be successfully prepared on the tip of tungsten needles with the arc radius of 100 nm and 300 nm, respectively.