A new technology developed by scientists at Northwestern University in Evanston could give an upgrade to a new generation of hydrogen-powered cars. The product, named NU-1501, acts as a bath sponge and is capable of holding and releasing large quantities of gas at lower pressure and cost.
A gram of the new aluminum-based material is said to have a surface area the size of a football pitch, as it contains billions of tiny pores. Researchers say it can store large volumes of gas one would typically need for practical travel without the need for expensive tanks.
Over the years, car sales, especially larger SUVs, have boomed in the United States as consumers gain interest in the cars. In 2017, carbon dioxide emissions from trucks, cars, trains, and airplanes, caught up with power plants as the most abundant supply of US greenhouse gas emissions.
Aside from the establishment of electric vehicles, many have focused on hydrogen as a zero-emission source of power for cars. As it proves to be considered a more 'greener' fuel when produced using renewable energy, hydrogen is sought out to power fuel cells in some cars and trucks.
Drawbacks of Hydrogen Vehicles
Although seemingly a better option for the environment, hydrogen vehicles do come with setbacks.
One of them being that hydrogen gas is exceptionally light. To carry 1 kilogram of hydrogen to power a car for over 100 kilometers, a tank capable of holding around 11,000 liters would be necessary.
In an attempt to solve the problem, the gas is usually stored at a high pressure to allow cars to carry four to five kilograms of the gas and travel up to 500 kilometers before needing to refill. The said level of pressure is around 300 times greater than in a car's tires and calls the need for custom-made tanks, which could add to the value of the vehicle.
Researchers believe they have worked out an alternative method that would allow the storage of high volumes of hydrogen under much lower pressure.
NU-1501
A team of scientists from Northwestern University has created an extremely porous material, described as a metal-organic framework. The product they called NU-1501 has been built from organic molecules and metal ions, which self-assemble to form highly crystalline, porous structures.
Professor Omar Farha, the leader of the research from Northwestern University, likened their product to a bath sponge, except it had arranged cavities. He explains how the material uses pressure to store and release the gas molecules, similarly to how a sponge absorbs water when you wipe it.
Farha says that the main ability of the new framework is that it can potentially store hydrogen and other gases at much lower pressures without the need for an enormous tank.
His team has acquired experience in developing these absorptive materials for the US Department of Defense to protect soldiers against nerve gas attacks.
The researchers claim there is currently funding available to develop this type of material for transport applications. The new material has already overpowered tough targets set by the US Department of Energy for onboard storage and delivery systems for other fuels. To allow further advancement, scientists will need significant buy-in from car manufacturers.
