What is the Electrokinetic effect?
The entire wikipedia article is a modest single paragraph long. Flowing salty water can make electricity, basically, if you can flow it over an electrode correctly.
Electrokinetic phenomena are a family of several different effects that occur in heterogeneous fluids, or in porous bodies filled with fluid, or in a fast flow over a flat surface. The term heterogeneous here means a fluid containing particles. Particles can be solid, liquid or gas bubbles with sizes on the scale of a micrometer or nanometer. There is a common source of all these effects—the so-called interfacial 'double layer' of charges. Influence of an external force on the diffuse layer generates tangential motion of a fluid with respect to an adjacent charged surface. This force might be electric, pressure gradient, concentration gradient, or gravity. In addition, the moving phase might be either continuous fluid or dispersed phase.
Well, I bet you feel informed now!
Why I’m bringing this to your attention is because of the following paper i read this week:
Energy conversion via metal nanolayers
Rather innoclus title, the gist is that flowing salty-water over rusty iron nanofilms can result in a voltage. The idea is that charged ion in the fluid can pull their “mirror” counterparts in the metallic layer. The idea isn’t new, it has been previously observed in graphene and CNTS.
What’s cool about this is the potential scalability:
Covering kilometers squared of a substrate in rusty metal wouldn’t be particularly difficult or expensive…
Worth checking out!
Phys.org on the ball: Ultra-thin layers of rust generate electricity from flowing water
Puzzle for you: Can you work out why this works on nanofilms, but not macroscopic films?!?
https://www.reddit.com/r/ireland/comments/bl1dez/waves_in_donegal/
The power of the ocean! The confusing perspective is lens compression.
