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Photo/Electro - dissociation

  1. Jun 14, 2008 #1
    I'm working on a project to split water. The idea is to have a spherical container of aluminum with the inside given a mirror finish. A germicidal light is secured inside and the container is filled with water.

    The UVC light should have enough energy to break the bonds (although I searched the internet and couldn't find a solid answer on the energy required to break the HO bonds) especially when the light is reflected back onto itself.

    However I know this won't actually cause hydrogen and oxygen gas to form but instead it will cause the water to undergo a cyclic process of bonds breaking and reforming involving the temporary formation of hydrogen peroxide.

    So that is where the electrolysis comes in. Electrolysis is a wasteful means of splitting water where current will simply pass through, some of the energy simply heats the water, then finally you get the energy that breaks the bonds and even a bit more to form the gases.

    My hypothesis is that once the UVC light breaks the bonds creating the ions, a much smaller current is used to pull these ions to the associating electrode (before any bond cycling can occur) where they pick up/drop off the necessary electrons to form the gases. That is once the bonds are broken, hydrogen ions will be pulled to the cathode where the ions pick up their missing electrons, come together to form hydrogen gas, and float to a collecting point. Oxygen ions will get pulled to the anode where they dump off the excess electrons, form oxygen gas, and float to a collection point.

    I'm hoping that 1 amp per second can produce 1/2 a mole of hydrogen gas per second and 1/4 a mole of oxygen gas per second. Provided that no current is required to do the bond breaking and that no current wastefully spans across from electrode to electrode without contributing to the process. This would mean that a small force (1 volt) can produce a large quantity of gas provided that the resistance is low (.01) resulting in a high current (10 amps).

    So what I'm looking for is some input, I would like to know the obstacles I may face before I get to them.

  2. jcsd
  3. Jan 6, 2009 #2
    Have you had any success with your prototype? I came up with the same idea(feb2008) and built a prototype out of aluminum but I found the metal to corrode very fast. I was also losing any gas I produced from a bad design.

    I have almost finished my new cell with stainless steel.

    I am very interested in any progress you have made

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