Basic research in artificial photosynthesis

  • I wonder if anybody ever told them that if you take a layer of doped activated carbon and put it in a dish and cover it with a layer of suitable electrolyte and put electrodes connected to a discharged capacitor in there and stand it out in the sunlight it will make a little oxy-hydrogen and slowly charge the capacitor too. I doubt it really, since I was AFAIK the first person to notice it. It's the infra-red component in the sunlight I suspect.

  • I wonder if anybody ever told them that if you take a layer of doped activated carbon and put it in a dish and cover it with a layer of suitable electrolyte and put electrodes connected to a discharged capacitor in there and stand it out in the sunlight it will make a little oxy-hydrogen and slowly charge the capacitor too. I doubt it really, since I was AFAIK the first person to notice it. It's the infra-red component in the sunlight I suspect.


    Thank for this. Do you have an idea of the chemical reaction going on here?

  • It is electro-chemeical dissociation. My speculation is that the carbon grains (put simply) become charged like batteries, They are the simplest kind of solar cell, some of the current is drained away by the 2 electrodes and charges the capacitor, some is used to dissociate the water, probably via - Step one H2O -> H+OH then Step two 4(H +OH) = 2H2O + 2H2 + O2.


    This is a slow process, which is probably why it has been overlooked - also you need to mess a bit with the carbon first, and then have the right conditions of bright direct sunlight to trigger it - which is not common in a laboratory. The conditions for electron transport are far from optimal. but Interestingly enough the presence of the capacitor seems to boost rather than reduce gas formation. From memory the typical electrode potential difference is around 0.4V - which is way below the 2V Faraday limit for electrolysis.

  • That is an interesting question to explore whether there are any synergies between Hydrogen producing photo-electrodes and LENR.


    By the way: after slandering Martin Fleischman on camera in '89, Nathan Lewis went on to collect funding for exactly this type of photoelectrochemical H2 production research.

  • Andras


    There are many synergies between catalysis and LENR for sure. Many of the principal materials are also used extensively as catalysts, nickel,palladium, zirconium, a long list. And perhaps you might regard photosynthesis as a closely connected to electro-chemical catalysis.

  • This device utilizes perovskite layers, which are unstable even on dry air - not to say under water. I.e. it's just another "five-minutes" lab study, which couldn't have any utility in praxis. It's always more perspective to develop solar cells optimized to solar/electricity conversion in tandem with efficient electrolyzer than to attempt to combine both into single device.