Researchers at RIKEN Quantum Optodevice Laboratory have developed a highly efficient LED that can kill microbes and viruses but is safe for humans
Ultraviolet germicidal lamps are capable of killing bacteria and viruses and are routinely used in hospitals to sterilize surfaces and medical instruments. But, these lamps produce ultraviolet light in a range that damages DNA and hence is very harmful to be used around people. To overcome this problem, three physicists at RIKEN Quantum Optodevice Laboratory, Masafumi Jo, Yuri Itokazu, and Hideki Hirayama, created an LED that could effectively exterminate viruses and bacteria without harming human beings.
The researchers integrated multiple layers, each containing slightly different proportions of aluminum. Further, in some layers, they also added tiny amounts of silicon or magnesium. This created an obstacle course for electrons, obstructing their movement across the material and trapping them for longer in certain areas. This is revealed in an increased amount of light emitted by the device and a reduced amount absorbed by it.
The team analyzed the procedure using computer simulations to model all possible effects to help pin down the ideal design. “We then grew samples to see if it was effective or not,” Jo says, physicists from RIKEN Quantum Optodevice Laboratory. Accurately limiting the thickness of each layer was a significant challenge. It resulted in an LED operating in the far ultraviolet, with an output power almost ten times higher than their previous best.
The COVID-19 pandemic revealed the importance of being able to eliminate viruses and microbes on surfaces. “We trust that our findings and technologies will be very useful for safeguarding society against this and future pandemics,” says Jo.
Jo adds that the trio wants to enhance their LED’s performance. “There’s still much room for improvement in the output power and the power efficiency,” he notes.
Click here for the Published Research Paper