Each mol of silicon should produce 2 mol of H2 but the article says they obtained 2.58 mol. How is that possible? TheChemiKid - 25-6-2014 at 17:57
I'm not sure how that is possible, I think it might be a mistake, but this is really interesting.Zyklon-A - 26-6-2014 at 09:28
Weird. Perhaps more than one reaction is occurring [giving rise to different oxidation states or silicon hydroxides, thus a different stoichiometry is
involved] - to small extents of course.
It seems like a decent idea, but nano-silicon particles are far too expensive to make for the energy you get out of the cell.
I like the idea of adding a few % of lithium or sodium hydride to catalyze the reaction. That seems beneficial.
Perhaps there would be no need for the particles to be that small if alloyed with alkali hydrides. >100-nm silicon nanoparticles, mixed
with 2-5% hydride ions would likely react as fast as the 10-nm pure silicon nanoparticles. [Just a thought]
[EDIT] Never mind, silicon cannot have a higher oxidation state than 4+, so there must be some mistake.
[Edited on 26-6-2014 by Zyklon-A]Artemus Gordon - 26-6-2014 at 12:18
Since Oxygen binds with itself during electrolysis, I'm guessing they are getting some O2 in addition to SiO2.blogfast25 - 26-6-2014 at 13:13
Each mol of silicon should produce 2 mol of H2 but the article says they obtained 2.58 mol. How is that possible?
Well spotted. It does seem to be a mistake: Si can never generate more than 2 mol of H2 per mol of Si, no matter what the source of hydrogen is...
unless the reaction product behaves catalytically for the splitting of water.Morgan - 26-6-2014 at 17:23
The explanation is somewhat vague to me. Had some of the remaining Si formed a hydride? Or are they saying it was just a bunch of bubbles that weren't
dislodged at the initial start of the measurements, giving the experiment a head start so to speak? Or as mentioned is it implying a catalytic bonus?
Or was it that the way the nano silicon was manufactured that it contained residual hydrogen that is first released/driven off before the water starts
breaking down? There is this chart. http://bioage.typepad.com/.a/6a00d8341c4fbe53ef017d402119299...
"In addition, the hydrogen generated from the 10 nm silicon exceeds the expected 2 mols of H2 per mole of silicon. They attributed this to to the
presence of hydrogen on the surface of the particles remaining from their production in a hydrogen rich environment." http://www.greencarcongress.com/2013/01/ergbogbo-20130118.ht...
