Development of High-resolution Mobility System and Structural Control of Nanocarbon Materials.

离子迁移系统已被用于分析气溶胶粒子或团簇的结构。该测量系统在阐明新结构方面具有许多优势，但尚未应用于观察“长期变化”，这对纳米碳材料的应用至关重要。在这个研究项目中，我们成功地开发了一种新型离子迁移系统，实现了2小时以上的长期观察。该系统由堆叠的环形电极组成，其中用于粒子阱的RF电场（600Vpp, 20kHz）和用于迁移率测量的LF电场（9Vpp, 2.5Hz）被应用。该系统在环境条件下利用了两个离子阱，这是该系统的新特点。用这个系统对带电粒子进行了两个多小时的观察。粒径为10um， m/z=2×10^8的颗粒由浓度为5 ~ 27wt的NaCl水溶液制备。%（饱和溶液）由雾化器施加10kV。在LF场诱导的上下运动中捕获了更多的细胞，并对其进行了分析。捕获的粒子用激光照射，并用数码相机进行监测。由于颗粒粒径越大，其迁移率和移动幅度越小，因此通过LF场诱导的移动幅度来分析颗粒的大小。系统中的颗粒通过吸收空气中的水蒸气和颗粒中的水分蒸发，在小时的时间尺度内逐渐改变其大小。粒径变化趋势强烈依赖于NaCl浓度，说明该系统可以灵敏地分析纳米碳材料的长期演化过程，如生长过程。这些结果表明了该系统的潜力，新开发的大型系统将增强该系统的潜力。新开发的系统可以容纳和移动500毫米长的捕集器颗粒。该系统通过对外加电场引起的长时间运动和重力引起的自由落体运动的混合监测，可以精确地确定颗粒大小和电荷量，具有较高的分辨率。该系统还配备了离子漏斗，以增强离子从粒子源到其他测量系统（如质谱仪）的转移。具有高分辨率和高灵敏度，为纳米碳材料的监测和控制奠定了基础。少

The Ion Mobility System has been utilized to analyze structures of aerosol particles or those of clusters. This measurement system provides lots of advantages to clarify the new structures but has not been applied to observe "long-term changes", which is crucial for the applications of nanocarbon materials. In this research project, we have succeeded to develop a new type ion mobility system achieving long term observation for more than two hours.The system consists of stacked ring electrodes where an RF electric field (600Vpp, 20kHz) for the particle trap and an LF filed (9Vpp, 2.5Hz) for the mobility measurement were applied. This system utilizes the two ion traps in ambient condition, which is novel feature of the systems. With this system charged particles were observed for more than two hours. The particles (diameter=10um and m/z=2×10^8) were produced from NaCl water solution with concentration from 5 to 27wt. % (saturated solution) by an atomizer where 10kV was applied. The parti … More cles were trapped and were analyzed with up-down movements induced by LF filed. The trapped particles were irradiated by a laser and were monitored by a digital camera. The particle size were analyzed by the amplitude of the movement induced by the LF field since the larger the particle size is the smaller the mobility and the amplitude are.The particles in the system gradually changed its size in the time scale of hours through absorbing water vapor from the air and vaporization of water of the particles. The trend of the particle size change strongly depends on the concentration of the NaCl, which clarified that the system can analyze long-term evolution such as growth processes of nanocarbon materials sensitively.These results show the potential of the system, which will be enhanced by the newly developed larger system. The newly developed system can hold and move particles with a 500mm long trap. This system has much higher resolution and can determine the particle size and the amount of charges precisely with the hybrid monitoring of the long movement induced by the applied electric field and free fall movement induced by the gravity. The system is also equipped an ion funnel which enhances the transfer of the ion from the source of the particle and to other measurement system such as mass spectrometer. With the high resolution and sensitivity, we are ready to monitor and control of nanocarbon materials. Less