Size-dependent electro-osmosis in a microchannel with low-permittivity, salt-free media

作者：Chang Feng Ming^*; Chang Yi Wen; Sheng Yu Jane; Tsao Heng Kwong

来源：Applied Physics Letters, 2010, 97(16): 164101.

DOI：10.1063/1.3502601

Electro-osmosis is the preferred transport mechanism in microfluidic systems. The electro-osmotic mobility in an aqueous solution is essentially independent of the microchannel size. However, in low-permittivity solvents, the screening effect is absent and the mobility is found to grow with the capillary radius according to our analytical theory and electro-osmotic flow experiments. Our results show that regardless of low surface charge density, electro-osmosis always occurs for long enough microchannels. Therefore, electro-osmosis provides a method for determining extremely low surface charge density associated with low-permittivity media. The implication in the response time of electronic paper is given as well.

• 出版日期2010-10-18
• 单位中央民族大学