Scientists create cheaper, high performing LED

New York: Researchers at Florida State University have developed a new type of light-emitting diode, or LED that could lead to cheaper, brighter and mass produced lights and displays in the future.

Energy-saving LED lighting is already sold in stores, but widespread adoption has been slow because of the costs associated with the material and the quality.

"We came up with our novel approach to solve some critical problems and get a high-performance LED," said associate professor Biwu Ma.

The researchers used an organic-inorganic hybrid form of the material perovskites to build the highly functioning LED. 

Perovskites are any materials with the same type of crystal structure as calcium titanium oxide. Other researchers experimented with perovskites to build LEDs in the past but could not build particularly effective ones. 

The researchers believed this organic-inorganic hybrid could perform better, if the formula could be appropriately tweaked.

After months of experiments using synthetic chemistry to fine tune the material properties and device engineering to control the device architectures, they ultimately created an LED that performed even better than expected.

The material glowed exceptionally bright.

It is measured at about 10,000 candelas per square metre at a driving voltage of 12V. Candelas are the unit of measurement for luminescence. 

It was also quick and easy to produce.

The researchers said they can produce the material in about an hour in the lab and have a full device created and tested in about half a day.

Additionally, while bare hybrid perovskites tend to be unstable in humid air, the nanostructured perovskites exhibit remarkable stability in ambient environment because of the purposely designed surface chemistry.

Such chemical stability largely reduces the requirement of sophisticated infrastructure to produce this new type of LEDs and could be of huge benefit for cost-effective manufacturing in the future.

The findings appeared in the journal Advanced Materials.