Usually, to get hydrogen, the first method that you think of is the electrolysis of water. However, this is not the most efficient way to get the precious energy-carrying gas, and as hydrogen cars will slowly emerge on the market it will need production efficiency, not only the mere fact that it works.
So far, electrolysis has been made more efficient through catalysis like platinum or gold, but these are too rare and hence expensive to make the technology successful on a wide scale. Heat-driven electrolysis, on the other hand, is an alternative, but so far experiments have been too expensive, toxic and corrosive at the same time.
Mark Davis from Caltech invented a new method of splitting water that isn’t corrosive and doesn’t use toxic intermediate products to work.
His method, instead of using heated oxidized metal to drive off the oxygen from water, uses magnesium oxide. The reactions are facilitated by shuttling ions in and out of it. The use of sodium decreases the temperature needed for the reaction to 850 degrees Celsius, versus the 1,000 degrees needed in other cases.
However, the technology is still in its early infancy and needs further development (and the money for it) to work properly and be sustainable. For example, they only succeeded to recycle the magnesium five times, but hope that one day they’ll be able to do it for thousands of times, so the word “recyclable” to really deserve its meaning. “All we did here is prove the chemistry could work,” says Davis.
Hydrogen powered cars are a thing of the future – but not a distant future. Technologies like water splitting have to become mainstream as fast as possible. When they do, hydrogen cars will probably outperform battery-powered ones in both range and cleanness, because they only emit water from their tailpipes.