As discussed in an article by Science Daily, a recent scientific discovery could change the way that pure hydrogen is extracted from water, making the element much cheaper to procure as a source of fuel.
Hydrogen is traditionally acquired by extracting it from water through the process of electrolysis, in which a direct current is sent into the liquid to set off a chemical reaction. Currently, the United States produces 100 billion cubic feet of hydrogen annually. While water is simple to acquire for this process, the difficulty comes from the need to use costly noble metals, such as platinum and palladium, for the water-splitting process.
Through efforts to lower the costs of the hydrogen reaction, chemistry professor Song Jin of the University of Wisconsin-Madison spent time researching the use of iron pyrite (fool’s gold) and other inexpensive metals for the transformation process. The catalyst she and her students discovered contains common elements phosphorus and sulfur, along with cobalt, a metal that is 1000 times cheaper than platinum. They created this by replacing the iron in fool’s gold to make cobalt pyrite, and then added phosphorus.
|Fool's gold (iron pyrite) was used to create the catalyst.|
As a substitute for using electricity to separate the water, Jin also proposes that the process be executed by using direct sunlight, a method that is compatible with her high-performance catalyst. However, she does admit that her new catalyst has only worked so far in the laboratory stage, and more research will be necessary to determine how exactly the method of using it can be implemented. While the performance of this catalyst in sunlight is very close to that of using a platinum electrolyser, it does not exactly match up. The catalyst is ideal for those who are willing to sacrifice some of the performance to significantly lower the cost.
Electrolysis of water to create hydrogen can be an important factor in lowering dependence on oil and methane. However, even though the use of hydrogen does not release carbon dioxide into the atmosphere, burning it does release water vapor, which is also a greenhouse gas. According to NASA, water vapor is actually the world’s most abundant greenhouse gas, but its effects on the climate are difficult to understand. The only other waste product from this process is liquid water.
Several standards available from ANSI currently provide guidelines for the separation of hydrogen from water for fuel. ISO 22734-1:2008: Hydrogen generators using water electrolysis process - Part 1: Industrial and commercial applications provides guidelines for the use of electrolysis to produce hydrogen gas to generate electricity for industrial purposes. For the use of home hydrogen generators, there is ISO 22734-2:2011: Hydrogen generators using water electrolysis process - Part 2: Residential applications. The gas produced through the processes in either of these standards can be used the moment it is created or can be stored for later use.