Hybrid ‘Wonder Material’ Creates Efficient LEDs

A new type of perovskite — touted as a “wonder material” — has been used to create a new type of LED that has the potential to create more efficient light sources than those that rely on conventional solar cells.

A team from the University of Cambridge, the University of Oxford and the Ludwig Maximilian University of Munich has developed a new type of perovskite called organometal halide perovskite containing a mixture of lead, carbon-based ions and halogen ions.

“These organometal halide perovskites are remarkable semiconductors,” said lead researcher Zhi-Kuang Tan, a PhD candidate at the University of Cambridge's Cavendish Laboratory.

Perovskite-based LEDs. Courtesy of Zhi-Kuang Tan/University of Cambridge.

“We have designed the diode structure to confine electrical charges into a very thin layer of the perovskite, which sets up conditions for the electron hole capture process to produce light emission,” he said.

The new LEDs were made using a simple, scalable process in which a perovskite solution was spin-coated onto a substrate. The process should be inexpensive to manufacture on a large scale, according to the researchers, as it does not require additional steps.

The new hybrid material can be tuned to emit light in a variety of colors as well, making it useful in the development of flexible color displays, lighting and optical communication applications.

“This technology could provide a lot of value to the ever growing flat-panel display industry,” Tan said.

Now, the researchers are working to increase the new LEDs’ efficiency and potentially use them for diode lasers. The first commercially produced perovskite-based LEDs could be available within the next five years, they said.

The research was published in Nature Nanotechnology. (doi: 10.1038/nnano.2014.149).

For more information, visit www.cam.ac.uk.