# Effect of solvent polarization on electroosmotic transport in a nanofluidic channel

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## Abstract

In this paper, we develop a theory based on the Langevin–Bikerman approach to study the electroosmotic (EOS) transport in a nanofluidic channel in the presence of finite solvent polarization effect (SPE). At the outset, we conduct an analysis based on practically achievable parameters to highlight the consequence of SPE in the variation in the electric double-layer (EDL) electrostatics. We witness that SPE invariably increases the effective EDL thickness; our numerical results are justified through a scaling analysis. More importantly, we unravel that the EOS transport, most remarkably, shows negligible influence on the qualitative variation in the EDL electrostatic potential; rather, it is dictated by the ratio of the effective to the actual EDL thicknesses. This finding, supported by scaling analysis, ensures that for the chosen set of parameters, SPE invariably enhances the EOS transport. Apart from shedding light on this extremely non-intuitive nanoscopic electroosmotic flow phenomenon, we anticipate that the present study will embolden us to better control the nanofluidic transport for a plethora of biological and industrial applications.

## Keywords

Zeta Potential Electrostatic Potential Stern Layer Water Dipole Electroosmotic Velocity## Notes

### Acknowledgments

Shayandev Sinha acknowledges Laboratory of Physical Sciences (LPS) for partly supporting his graduate studies.

## References

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