Enhanced voltage generation through electrolyte flow on liquid filled surfaces*

The generation of electrical voltage through the flow of an electrolyte over a charged surface may be used for energy transduction. Here, it is shown that enhanced electrical potential differences/streaming potential may be obtained through the flow of salt water on liquid filled surfaces infiltrated with lower dielectric constant liquid, such as oil, harnessing electrolyte slip and associated surface charge. A record of large figure of merit, in terms of the voltage generated per unit applied pressure, of 0.043 mV/Pa, is obtained through the use of the liquid filled surfaces, greater by a factor of 1.4, when compared to air filled surfaces. These results lay the basis for innovative surface charge engineering methodology for the study of electrokinetic phenomena at the microscale with applications to new electrical power sources.