Crystal storage for CO2 and hydrogen

Metal-organic frameworks (MOFs) are porous crystalline structures capable of storing gases, such as carbon dioxide, methane or hydrogen, in tight spaces.

Since the 1990s when MOFs were invented, researchers have been making strides in how much gas the structures can hold. They've done this by increasing the crystal's surface area through intensifying its porosity.

Publishing this month in the journal Science, chemists at UCLA's California NanoSystems Institute and Soongsil University in Seoul, South Korea report how they have broken the record for the porosity of a nano-material. Apparently, twice as many very tiny cavitities are now possible in the very tiny crystals of MOF-200 and MOF-210.

With twice as many holes, the nano-materials can store twice as much gas. And one gram of the new crystals—about the size of four sugar pills—goes a long way, according to the researchers.

The AP quotes Omar Yagh, the study's senior author:

If I take a gram of MOF-200 and unravel it, it will cover many football fields, and that is the space you have for gases to assemble. It's like magic. Forty tons of MOFs is equal to the entire surface area of California.

Earlier this year, SmartPlanet's Andrew Nusca discussed some of the researchers' previous work (see: Chemists create synthetic 'gene' to capture carbon dioxide)

According to a statement, low-cost ingredients such as zinc oxide and terephthalate, found in plastic bottles, can comprise MOFs, which can be specified to trap certain gases. The researchers hope industrial applications for the crystals could include helping capture emissions of carbon dioxide, a greenhouse gas, and storing hydrogen as a fuel.

BASF, a German company that produces large amounts of MOFs, helped fund the study.