Measurement of the Electrostatic Charging State of Individual Particles in Ambient Aerosol Using Kelvin Probe Force Microscopy
Measurement of the Electrostatic Charging State of Individual Particles in Ambient Aerosol Using Kelvin Probe Force Microscopy
复制标题
使用开尔文探针力显微镜测量环境气溶胶中单个颗粒的静电充电状态
DOI：
10.11203/jar.30.190
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
I.W.
中科院分区：
文献类型：
--
作者：
奥田知明，郡司裕真，Lenggoro;I.W.
近年来，人们提出了静电充电状态对人体气道中颗粒沉积的重要性。在这项研究中，我们开发了一种使用开尔文探针力显微镜（KPFM）测量单个环境气溶胶粒子静电充电状态的方法。对于KPFM基板，玻璃板比聚四氟乙烯或聚碳酸酯过滤器更合适。我们在玻璃板上收集了基本电荷数在4 ~ 11之间的带电聚苯乙烯乳胶标准粒子，并用KPFM测量了形貌和表面电位。将颗粒顶部与玻璃基板表面之间的表面电位之差确定为颗粒表面电位。带正电的粒子表面电位为+ 50 mV，带负电的粒子表面电位约为-45 mV。对于环境气溶胶粒子，表面电位范围为-56.6 mV ~ + 156.7 mV，表明本研究分析的环境气溶胶粒子的基本电荷数大于4。对单个气溶胶粒子进行KPFM和SEM/EDX的序列分析有助于发现单个粒子的表面电位和化学成分之间的关系。
Recently, the importance of electrostatic charging state to particle deposition in the human airways has been suggested. In this study, we developed a measurement method of electrostatic charging state of individual ambient aerosol particles using Kelvin probe force microscopy (KPFM). For KPFM substrates, glass plates were more suitable than PTFE or polycarbonate filters. We collected charged polystyrene latex standard particles with the number of elementary charges between 4 to 11 on the glass plate, and measured the topography and the surface potential using KPFM. The difference in surface potential between the particle top and the glass substrate surface was determined as the particle surface potential. The particle surface potential for positively charged particle was+ 50 mV and that for negatively charged particle was approximately-45 mV. For the ambient aerosol particles, the surface potential ranged from-56.6 mV to+ 156.7 mV, indicating that the number of elementary charges of ambient aerosol particles analyzed in this study was more than 4. Sequential analysis of KPFM followed by SEM/EDX for a single aerosol particle would be useful to find the relationship between the surface potential and chemical composition of individual particles.