Current conduction and fluid flow in nanochannels with overlapped double layers for surface characterization and electrokinetic power generation

摘要

The net flow of an aqueous solution established within a channel will carry both charged and uncharged species in the solution downstream; the transport of net charges in the latter case, in principle, can give rise to an electric current, known as the 'streaming current'. This effect is particularly significant in microscale and nanoscale channels fabricated out of materials such as glass and plastics which acquire a surface charge in contact with aqueous electrolyte solution.~(1-3) In some applications, arrangements are made to drain this current through electrodes and an external resistor; in other applications, the electrodes are left externally unconnected (i.e. in the open circuit condition) and in yet another group of applications, the electrodes are short-circuited.