Researchers at MIT have discovered a material that can switch between two crystal states by applying a small voltage.

This is a significant finding which could provide a new nonvolatile computer memory chip which could be used in energy conversion or catalytic applications as well.

The experiment uses a thin-film material called strontium cobaltite, or SrCoOx. When voltage is applied to it, changes in oxygen content create two crystal states with different chemical, electrical, magnetic and physical properties: browmillerite and perovskite.

The material can be switched back and forth by applying as little as 30 millivolts, but remains stable until another voltage is applied. 

To demonstrate the material’s transformation from one phase to another, the researchers used in-situ X-ray diffraction when applying voltage.

Applications for Strontium Cobaltite

Strontium cobaltite is one of many metal oxides which can be used for applications such as electrodes in fuel cells, gas separation, and electronic memory devices.

Now, with different material properties elicited from small voltage changes, even more applications can be added to the list.

Gas pressure and temperature changes have also been used to achieve a switch between different materials. However, in comparison to temperature and gas pressure changes, the electrical voltage approach is more practical for devices in use today.

Using the electrical charge method for material phase change can lead to further advancements in fuel cells and electrodes for lithium ion batteries.

Nanotechnologists commented that new kinds of memory devices are possible with this research as well as higher efficiency of energy conversion in electrochemical devices.

The research underway aims to fully understand the electronic properties of the reshaped materials and to perform additional experiments with other metal oxides used for memory and energy applications.