Chromium's bonding angles let oxygen move quickly
Wednesday, September 3, 2014 - 08:01
in Physics & Chemistry
By taking advantage of the natural tendency of chromium atoms to avoid certain bonding environments, scientists at DOE's Pacific Northwest National Laboratory have generated a material that allows oxygen to move through it very efficiently, and at relatively low temperatures. Specifically, they found that their attempts to make metallic SrCrO3 lead instead to the formation of semiconducting SrCrO2.8. Because chromium as an ion with a charge of +4 does not like to form 90º bonds with oxygen, as it must in SrCrO3, SrCrO2.8 forms instead with a completely different crystal structure. This material contains oxygen-deficient planes through which oxygen can diffuse very easily.
