The philosopher's stone for a new era: quest for a cheap hydrogen economy
Ages ago, alchemists sought a philosopher's stone, reputed to be capable of turning any metal into gold. We now know that materials cannot transmute magically into other materials, but the quest to harness the magic of chemistry to create value out of inexpensive materials has never been better represented than in the modern field of catalysis underpinning hopes for achieving a hydrogen economy to replace our current dependence on fossil fuels.
A catalyst works a bit like a scientist of old might have imagined the philosopher's stone would. For example, passing water over a catalyst can "magically" transform that water into hydrogen and oxygen at much lower energies than if we tried to tear the H away from the O in H2O without the catalyst.
Thus the modern dream is born: if we could just get hydrogen out of abundant water, we could burn it for heat or use it in fuel cells to power our cars and factories or store energy in the form of hydrogen at wind and solar farms. The hydrogen economy has many hurdles, but remains one of the scientifically attractive options to get us beyond the current capriciousness of alternative energy as well as the limitations of electric cars with batteries.
One big hurdle: most of the catalysts known to be effective in splitting water are based on rare and expensive noble metals, like platinum.
The newest entry in the race for a cheap, efficient substitute for noble metals -- a cobalt-phosphorous-sulfur based complex -- appeared this month in Nature Materials. Of course, the research foundation immediately sought a patent, "because this new catalyst is so much better and so close to the performance of platinum", in the words of University of Wisconsin chemistry professor Song Jin.
Can we even dream of a combination of catalyzed hydrogen electrolyzer efficiency and automotive efficiency such that we could pump water into our vehicles and they would run on the power of the sun? Well, that might be a bit like hoping for a philosopher's stone. But hopes akin to magic are behind many of the scientific advances that have brought us where we are today.