  Electrokinetic energy conversion provides a scheme for energy harvesting and
storage for on-chip applications. However, the major drawback of electrokinetic
energy conversion is its low conversion efficiency. Researchers are in a quest
to find ways to improve this efficiency. With the same motive, we investigated
the generation of streaming potential by applying surface modification and
employing a non-Newtonian fluid to flow through the microchannel under constant
pressure difference across its ends. Shear-thickening liquids tend to lessen
electrokinetic effects, whereas shear-thinning liquids favour them. Also,
having superhydrophobic surfaces improve the magnitude of generated streaming
potential. We examine the combined effect of fluid rheology and surface
modification on electrokinetic energy generation. We have learned intriguing
insights about using non-Newtonian fluid in hydrophobic microchannels as an
outcome of our combined research. Hydrophobic surfaces do not enhance the
efficiency for a fluid with below a power law index of 0.7. The findings of
this research can be used towards the selection of fluid-substrate combination
that will optimize electrokinetic power generation efficiency.
