Brute force cracking of water into hydrogen and oxygen is just one of hundreds (if not thousands) of ways to create H2 gas. However, researchers at the Weizmann Institute’s Organic Chemistry Department in Israel have developed a method using water, metal, heat and sunlight to efficiently produce hydrogen and oxygen.
This new method does not use electrolysis, nor does it use chemical agents to cause the reaction. Professor David Milstein and colleagues have developed a method in several stages that ultimately breaks the bonds holding H2O together.
Other scientists have tried to recreate photosynthesis, nature’s most efficient way to separate water into hydrogen and oxygen with only marginal success. Professor Milstein exposes water in sequential steps to elemental ruthenium, heat and then sunlight, in that order.
Exposing water to ruthenium breaks the H2O bonds and releases part of the hydrogen with some left in an OH group binding to the metal center. In the heat stage, hydrogen is once again release with some OH once again binding to the ruthenium center.
In the third stage, sunlight is introduced which releases both oxygen and hydrogen and the ruthenium reverts back to its original state so it could be reused for further reactions. This is perhaps the most noteworthy part of the process since with other types of hydrogen generation methods using chemicals or metals there is most always degradation and the recycling process can be quite complex.
More research will be needed, but this staged approach to hydrogen production from water using no electrolysis or chemical agents offers hope for hydrogen cars. If this process can be scaled up then large amounts of hydrogen may be produce efficiently and cost effectively compared to other processes.