Far-Ultraviolet LED is proving to be a new weapon against the spread of superbugs. Three RIKEN physicists have developed this highly efficient LED that can kill microbes and viruses but causes no harm to humans.
Ultraviolet germicidal lamps are an excellent form of sterilization for many surfaces and instruments.
LEDs are energy efficient, however, they use ultraviolet light that can often damage DNA and cannot be used to light the area around people. Researchers are still working on LEDs that shine just within a narrow wavelength of far-ultraviolet light that both disinfects and is safe for people.
Germicidal LED lamps are often made from aluminum, gallium, and nitrogen. If you increase the amount of aluminum in these LEDs, they can be modified to work with a wavelength region that is safe for humans. They have been traditionally challenging to modify because it reduces their power.
The researchers at the RIKEN Quantum Optodevice Laboratory solved this issue by adding multiple layers containing different proportions of aluminum and silicon/magnesium to their LED.
Better electron movement leads to more light and less absorption. This is caused by an artificial obstacle course for them to cross through, making the product emit more light due to the artificial delay
The team created simulations to understand what type of design worked best and grew samples with this design to see if it was effective. The biggest challenge they faced in the project was controlling the thickness of each layer precisely. To handle this, they ramped up the brightness of an LED and used a wavelength almost ten times higher than their previous design.
“We trust that our findings and technologies will be very useful for safeguarding society against this and future pandemics.”
Developments in LED performance will be possible through increasing output power and improving power efficiency. Experts such as Jo are confident that there is still significant room for improvement.