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← 'Major discovery' from MIT primed to unleash solar revolution

OK, the story is you don't actually get hydrogen GAS out of this thing-

Although the catalyst does produce oxygen from water, it does not produce hydrogen gas (H2) that can be burnt in a fuel cell. Instead, water is divided into oxygen gas, positive hydrogen ions, and electrons that are transferred into another circuit.

A second electrode and a different catalyst will be needed to combine those electrons with the hydrogen ion to make hydrogen gas.

The conversion efficiency will go down as a result of this (as yet undeveloped) conversion process.

At present they are claiming a cell electrode voltage drop of 1.6 volt to 1 volt. This number is pro-rata with the cell efficiency (0volts=100% efficiency). The cell they're comparing it to is the standard Pt electrolysis cell which is at least 50% efficient making theirs 87%. This is a much better number that the current best which is 80% and comes with lots of downsides.

This certainly looks like it might go on to solve the problem of renewable energy storage if that second stage can be done efficiently and cheaply.

Edit. Sorry my numbers are wrong, overstated. I'll have to fix them later.

Permalink Sat, 02 Aug 2008 03:30:00 UTC | #211749