Materials scientists at the University of Wisconsin-Madison have taken the help of piezoelectric effect to harness random energy available in the atmosphere to turn water into usable hydrogen fuel. It might prove a simple, efficient method to recycle waste energy. The research team is led by Huifang Xu, who is a UW-Madison geologist and crystal specialist. They took nanocrystals of zinc oxide and barium titanate. These two nanocrystals were put in water. When these crystals received ultrasonic vibrations, the nanofibers flexed and catalyzed a chemical reaction. This whole process resulted in splitting the water molecules into hydrogen and oxygen.
“This study provides a simple and cost-effective technology for direct water splitting that may generate hydrogen fuels by scavenging energy wastes such as noise or stray vibrations from the environment,” the authors write in a new paper, published in the Journal of Physical Chemistry Letters. “This new discovery may have potential implications in solving the challenging energy and environmental issues that we are facing today and in the future.”
The researchers, led by UW-Madison geologist and crystal specialist Huifang Xu, grew nanocrystals of two common crystals, zinc oxide and barium titanate, and placed them in water. When pulsed with ultrasonic vibrations, the nanofibers flexed and catalyzed a chemical reaction to split the water molecules into hydrogen and oxygen.
But scientists didn’t utilize this electrical energy straightaway. They use this energy in breaking the chemical bonds in water to split oxygen and hydrogen. Xu explains, “This is a new phenomenon, converting mechanical energy directly to chemical energy.” Xu calls it a piezoelectrochemical (PZEC) effect. Why it seems that scientists are beating around the bush? Because chemical energy of hydrogen fuel is more stable than the electric charge. Storage of hydrogen fuel is easy and would not lose potency over time.
With the right technology, Xu foresees this method to be utilized where small amount of power is needed. Now we can imagine charging a cell phone while taking our morning walk or we can enjoy cool breeze that can power street lights. Xu says, “We have limited areas to collect large energy differences, like a waterfall or a big dam. But we have lots of places with small energies. If we can harvest that energy, it would be tremendous.”