We obtain analytical solutions for transport-induced-charge electroosmosis (TICEO) in a nanopore under steady-state and transient conditions, when the applied salt concentration difference $\mathrm{\Delta }{n}_0$ is much smaller than the average salt concentration $n_0$ under a moderate applied electric field $\mathbf{E}$. The TICEO velocity in an uncharged pore is found to be proportional to ${\left|\mathbf{E}\right|}^2$ and the concentration gradient $\nabla n_0$. For charged pores, we define a dimensionless parameter $\xi$, where TICEO governs the electroosmotic behavior over conventional electroosmosis attributed from electric double layers when $\xi \gg 1$, resulting in a net electroosmotic flow independent of the surface charge, making it suitable for alternating current (ac) pumping applications. Moreover, we estimate the characteristic time $\tau$ of TICEO development to be on the order of tens of picoseconds for a 1 M potassium chloride aqueous solution, which suggests that ac nanopore pumping using TICEO can be effective up to gigahertz frequency. Significantly, it is indicated that the maximum pumping flow rate can be achieved at an optimal pore aspect ratio ${\chi }_{\text{c}}=0.457$, providing important information to future experimental designs.

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• Electrokinetic flows
• Osmosis
• Nanofluidic devices
• Navier-Stokes equation