Nanotech Works For Hydrogen
Green Energy News
March 5, 2008
Hydrogen is everywhere on our planet, but it is not free to roam. It is always joined at the molecular hip with something else. It is a carrier of energy since it requires energy to break it away from a mate. But when free, hydrogen can be a fuel, a source of energy to do something, to do work.
Unfortunately as a carrier of energy hydrogen is not very efficient. It takes considerable energy to separate hydrogen from oxygen or carbon, for instance. By some estimates more energy is needed for separation than hydrogen will give back as fuel – with available technology that is.
Most hydrogen is taken from natural gas through a process called steam reformation. However, the separation of hydrogen from the hydrocarbon not only takes energy but can be a source of greenhouse gas emissions: the very thing hydrogen is supposed to avoid. According to Quantum Sphere, a company that is developing nanomaterials to aid in the production of hydrogen, the steam reformation of natural gas produces four pounds of greenhouse gases for every pound of hydrogen produced.
It is still possible for hydrogen to be the fuel of the future. Certainly those developing hydrogen fuel cells think so. Most of the focus of hydrogen development has been on the development and commercialization of fuel cells. To a lesser and less glamorous extent, has been the research and development of hydrogen storage and hydrogen production.
For hydrogen to be the fuel of the future – around which to build a hydrogen economy – the volume of hydrogen produced probably needs to increase dramatically compared with amount of energy required to do it, particularly in regard to the other prominent method of hydrogen generation, electrolysis. Electrolysis, the separation of water into hydrogen and oxygen by way of an electric current passing through it by way of electrodes, can use any energy resource including renewables, even nuclear power, thus it can be greenhouse gas free. For electrolysis to become this potentially cleaner method of generating hydrogen the volume of hydrogen produced per unit of energy – the efficiency of producing hydrogen – needs to improve.
QuantumSphere thinks it has the answer: Employ nanomaterials in electrolysis. Electrodes coated with nanomaterials have an extraordinarily high surface area on which to come in contact with water. The greater the contact surface area of the electrodes, the greater the contact with water, the greater amount of hydrogen can be produced with the same energy input.
Think of it this way. A piece of sandpaper has a greater surface area than a sheet of plain paper because of all the little hills and valleys of the pieces of grit adhered to the paper. Nanoscale particles adhered to a object increase its surface area to an even greater extent. QuantumSphere’s use of nano scale nickel and iron particles on a QSI-Nano NiFe™ enabled electrode has increased the surface area of a commercial electrode by more than 1000 times. (But don’t get too excited, don’t expect hydrogen production to increase by 1000 times.)
The company says that through the use of a new proprietary nano catalyst formulation, it has demonstrated production of hydrogen and oxygen in an alkaline electrolyzer with 85 percent efficiency under ambient conditions, making it a commercially viable replacement for fossil fuel-based production methods. That is, using nanoparticle-enabled electrodes electrolysis can compete with the steam reformation method of generating hydrogen from natural gas, but is cleaner.
This breakthrough brings the concept of generating clean hydrogen on demand at home to fuel vehicles closer to reality. Only an electrical connection and water would be needed, and that electrical connection could be from the grid or distributed generation such as a home solar or small wind system.
“Efficient hydrogen fuel generation enabled by QSI-Nano NiFe™ electrodes unlocks the potential to simplify the hydrogen infrastructure and accelerate fuel cell commercialization,” said Kimberly McGrath, Ph.D., director of fuel cell research, QuantumSphere, Inc. “We envision the consumer being able to refuel their vehicles at home from garage electrolyzer units using water and off-peak electricity at night and solar power during the day.”
More than vehicles the efficient generation of hydrogen by electrolysis could aid the generation of intermittent renewable energy such as wind, solar, and ocean energy. With instant-on, on-demand hydrogen generation, hydrogen could become a viable energy storage medium of excess generation capacity from these sources. Overnight wind power, generated but not consumed on the grid, could be stored in the form of hydrogen.
It has been said for years that nanomaterials will help the renewable energy industry. Already nanomaterials have made new solar electric products possible. Now nanomaterials look as though they could add a key piece to the hydrogen economy puzzle.
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