Sunlight-Based Water Splitting Technique Developed By University Of Colorado Boulder Team, Hydrogen Fuel Production Seen

The University of Colorado Boulder team devised a new process that could split the hydrogen and oxygen components of water in a more efficient way.

The CU-Boulder team discovered a new water-splitting technique, using the power of sunlight, which could lead to the wide use of hydrogen as a clean and environmental-friendly fuel in the near future.

In a paper authored by CU-Boulder Professor Alan Weimer and Associate Professor Charles Musgrave, a solar-thermal system was devised that is capable of concentrating sunlight using a mirror system atop a central tower.

The tower will then gather the heat that was generated by the vast array of mirrors before delivering it to a reactor induced with a chemical compound known as metal oxides.

Adding steam to the system through boiling water will force the oxygen component of water to adhere to the metal oxide surface, freeing up the hydrogen molecules that will be collected as a hydrogen gas.

"We have designed something here that is very different from other methods and frankly something that nobody thought was possible before. Splitting water with sunlight is the Holy Grail of a sustainable hydrogen economy," said Weimer, a professor from the chemical and biological engineering department of UC-Boulder.

Musgrave, on the other hand, reiterated that their new system is way different and much better than the other known water-splitting techniques. Most of the techniques used in splitting oxygen and hydrogen components requires change in temperature, which is not the case in the new CU method as pointed out by Musgrave.

"The more conventional approaches require the control of both the switching of the temperature in the reactor from a hot to a cool state and the introduction of steam into the system. One of the big innovations in our system is that there is no swing in the temperature. The whole process is driven by either turning a steam valve on or off," Musgrave said.

Using the CU method, hydrogen fuel could be produced efficiently. The lead authors of the paper pointed out that the amount of hydrogen produced for fuel cells is directly proportional to the amount of metal oxide and steam introduced in the system.

The team will study the proposed design that contains reactor tubes almost a foot in diameter and several feet long, which will be filled with metal oxides and will then be stacked on top of each other.