Technology could really use some more sustainable sources, and now researchers at the Queensland University of Technology (QUT) have turned to an unusual one. The team has shown that human hair from barber shops can be used to create OLED displays.
The vast majority of the human hair swept off the floors of hair salons the world over ends up in landfill. So, the QUT researchers decided to collect this waste material from a local barber and incorporate it into electronic devices.
Hair is a good source of carbon and nitrogen, which is useful for making light-emitting particles. The hair is processed and then burned at 240 °C (464 °F), leaving a material that has carbon and nitrogen embedded in it. The team then turns this material into carbon nanodots measuring less than 10 nanometers across.
The nanodots are then dispersed through a polymer, where they clump together into what the team calls “nano-islands.” It’s these groups that can be used as the active layer in an OLED device.
When a small voltage is applied, these nanodots glow blue. It’s not particularly bright, the team says, but it should still be useful for small-scale displays, like wearable devices.
“Human hair derived carbon dot-based organic light-emitting devices could be used for some indoor applications such as smart packaging,” says Prashant Sonar, an author of the study. “They could also be used where a small light source is required such as in signs or in smart bands and could be used in medical devices because of the non-toxicity of the material.”