Abstract
The electroosmotic flow pumps which are non-mechanical pumps consisting of a porous material and a pair of electrode have attracted a great interest of many scientists because of their simple structure. In the pumps, movement of counter ions by electrophoresis induces the electroosmotic flow of water within the pores of the porous material. However, generations of gases like hydrogen and oxygen and pH change are caused by electrolysis of water under direct current driving. Recently, alternating current driven electroosmotic flow pump using track etched membrane was proposed by us. From the measurement of zeta potential on the both surface of the membrane, asymmetry of the pump is considered to arise from the asymmetry of the counter ions on the both surfaces of membrane. In this study, rectification mechanism in the pump is proposed through measurement of asymmetry of electric current under alternative current driving, the zeta potentials and the hydrodynamic radius of the pores obtained by the streaming potential measurements.
