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[Image above] Credit: Science Magazine; YouTube

The world is becoming increasingly more connected—and so is our technology.

Just last week, I drove a car with a Bluetooth-paired dashboard interface that seemed to anticipate my every need. After pairing the car with my smartphone, the dash display automatically played my favorite music every time I got in the car, told me how traffic looked on the way to work every morning, and even mapped the car’s parked location on my phone’s map app when I went shopping—all without even so much as a prompt or command.

And that’s standard technology.

Last month, I reported that many of the latest high-tech inventions unveiled at the Consumer Electronics Show 2017 are cozying up to one another by integrating with the Internet of Things.

But the possibilities of having so many different components of technology integrated in our everyday lives still need multifunctional technologies to really seamlessly combine so many technologies into one smart environment.

Scientists are on it, however—a team at the University of Illinois at Urbana–Champaign (Urbana, Ill.), Electronics and Telecommunications Research Institute (Daejeon, Korea), and Dow Electronic Materials (Marlborough, Mass.) has taken a big step in this direction with the development of two-way LEDs that can both emit and harvest light.

Built from quantum dots connected by semiconductor nanorods, these two-way LEDs hold a lot of promise to develop integrated, responsive, and smart touchless display screens that can autonomously detect input, communicate with other screens, and so much more.

“These LEDs are the beginning of enabling displays to do something completely different, moving well beyond just displaying information to be much more interactive devices,” Moonsub Shim, materials science and engineering professor at the University of Illinois and leader of the study, says in a university press release. “That can become the basis for new and interesting designs for a lot of electronics.”

The LEDs can absorb and emit light via a thin film of asymmetrically organized quantum dots connected by nanorods each composed of three semiconductor materials. The nanorod collects electrons, and the quantum dots’ shells gather positive charges—which the quantum dots can use together to generate light.

And that entire charged particle process is reversible, too—meaning that the quantum dot–nanorod structures can also collect, in addition to generate, light energy.

“The way it responds to light is like a solar cell. So not only can we enhance interaction between users and devices or displays, now we can actually use the displays to harvest light,” Shim says in the release. “So imagine your cellphone just sitting there collecting the ambient light and charging. That’s a possibility without having to integrate separate solar cells. We still have a lot of development to do before a display can be completely self-powered, but we think that we can boost the power-harvesting properties without compromising LED performance, so that a significant amount of the display’s power is coming from the array itself.”

See more about this interesting research in the short Science video below.

The paper, published in Science, is “Double-heterojunction nanorod light-responsive LEDs for display applications” (DOI: 10.1126/science.aal2038).

Credit: Science Magazine; YouTube