‘Crystalline sponge’ can help capture CO ²

To sequester carbon dioxide as part of any climate-change mitigation strategy, the gas first has to be captured from the flue at a power plant or other source. The next step is just as important: the CO has to be released from ² .

whatever captured it so that it can be pumped underground or otherwise stored for the long term.

That second step can be costly from an energy standpoint. Materials currently used to capture CO ² have to be heated to release the gas.

But chemists at University of California, Los Angeles, say that a new class of materials they developed called metal-organic frameworks, or MOFs, hold promise for carbon capture. In the study, Omar Yaghi describes the performance of one MOF, which he says can free most of the CO ² it captures at room temperature.

Yaghi described a metal-organic framework as a “crystalline sponge”, a hybrid lattice of organic compounds and metal atoms that has a huge internal surface area where gas molecules can be absorbed. The MOF used in the study contains magnesium atoms, “which make just the right environment for binding carbon dioxide”, he said.

In experiments, the material separated out CO ² while allowing methane to pass. What was really surprising, though, was that at room temperature 87% of the CO ² could be released.

Pulp fact: Paper batteries to power laptops, drive cars

Ordinary paper could one day be used as a lightweight battery to power the devices that are now enabling the printed word to be eclipsed by email, ebooks and online news.

Scientists at Stanford University in California reported on Monday that they have successfully turned paper coated with ink made of silver and carbon nanomaterials into a “paper battery” that holds promise for new types of lightweight, high-performance energy storage.

The same feature that helps ink adhere to paper allows it to hold onto the single-walled carbon nanotubes and silver nanowire films. Earlier research found that silicon nanowires could be used to make batteries 10 times as powerful as lithium-ion batteries now used to power devices such as laptops.

“Taking advantage of the mature paper technology, low cost, light and high-performance energy-storage are realized by using conductive paper as current collectors and electrodes,” the scientists said.

This type of battery could be useful in powering electric or hybrid vehicles, would make electronics lightweight and long lasting, and might even lead someday to paper electronics, the scientists said.

Battery weight and life have been an obstacle to commercial viability of electric-powered cars and trucks.

“Society really needs a low-cost, high-performance energy storage device, such as batteries and simple supercapacitors,” Stanford assistant professor of materials science and engineering and paper co-author Yi Cui said.

Cui said in an email that in addition to being useful for portable electronics and wearable electronics, “Our paper supercapacitors can be used for all kinds of applications that require instant high power.” Peidong Yang, professor of chemistry at the University of California-Berkeley, said the technology could be commercialized within a short time.