Thanks to Alan Smith for letting me know about this interesting study by engineers from in which splitting and re-combining water in a microscopic system has the effect of creating a combustion engine on a tiny scale.
A description from the MIT Technology Review:
The new micro-combustion engine is simple in principle. It consists of a tiny chamber filled with water and containing a pair of electrodes attached to a circuit. Passing a current through the circuit causes the water to dissociate into oxygen and hydrogen, which then form nanobubbles.
Although these bubbles are too small to see, the volume of gas dramatically increases the pressure in the chamber, causing a membrane at one end to deform. This is what generates force.
When the current stops, the pressure drops rapidly. So quickly, in fact, that the researchers aren’t entriely sure why. It’s certainly too fast for conventional processes such as the gas diffusing out of the chamber or dissolving back into the liquid.
But Svetovoy and think they know what’s going on. Their idea is that when the current is switched off, the hydrogen and oxygen in the nanobubbles spontaneously combust, forming back into water. It is this combustion and the removal of the gas that causes the pressure to drop so rapidly.
Reading this descriptions makes me think about the HHO catalysis effects we have been discussing here recently, and I wonder what the connection to the observations found here might be.
The full study has been published on Arxiv.org, and can be read here.