Over the past 20 years, there has been a strong push to develop more efficient solutions for artificial lighting. Incandescent bulbs were the dominant technology for over 100 years, but by the 2000s, environmentalists concerned with the limited energy efficiency and waste generated by incandescent bulbs started promoting longer-lasting CFL bulbs, as well as LED lights. Lasting years longer than traditional incandescent bulbs, CFL and LED lighting generate much less waste over the same amount of time.
But there remains one major concern: They contain mercury, which poses a potentially significant health hazard if the bulbs are not safely discarded.
Enter graphene. A company based in Manchester, England, called Graphene Lighting first produced lightbulbs featuring LED filaments coated in graphene in 2015. The bulbs, which contain no mercury, are 10 percent more energy-efficient than LED lights, owing to graphene’s superior conductivity. Besides obviously being more environmentally friendly than their predecessors, the bulbs are also more durable, lasting 25,000 hours, and are more cost-effective.
Graphene was first developed by two Russian scientists, Andre Geim and Konstantin Novoselov, at the University of Manchester in 2004. The school’s deputy vice chancellor, Professor Colin Bailey, is one of the directors of Graphene Lighting, which was founded in 2014. The Canadian-financed company added a second plant, in Shenzhen, China, five years later.
That same year brought another graphene-related lighting development, as researchers at the Norwegian University of Science and Technology created ultraviolet light on a graphene surface for the first time. One of the researchers, Ida Marie Hoiaas, told Phys.org that such a product “could turn out to be cheaper and more stable and durable than today’s fluorescent lamps.”
“If we succeed in making the diodes efficient and much cheaper,” Hoiaas told Phys.org, “it’s easy to imagine this equipment becoming commonplace in people’s homes. That would increase the market potential considerably.”
According to that same outlet, the process began in a Japanese laboratory, where a layer of graphene was placed on glass. Through a process known as molecular beam epitaxy, nanowires composed of aluminum gallium nitride were grown on the graphene substrate, and the sample was shipped off to the researchers in Norway.
They constructed gold and nickel contacts on the graphene and nanowires. The graphene then served as the conductor when power was sent to the nanowires, which emitted the ultraviolet light. Graphene is transparent to all light, regardless of wavelength, so that which was produced in this case shone through the graphene, as well as the glass.
Not only is graphene a more cost-effective alternative to LEDs and CFL bulbs, it is also non-toxic, since it does not use mercury. Use of that element in fluorescent lighting has come under criticism from various organizations, including the UN, leaving industries scrambling to find new alternatives in order to meet new health and safety regulations.
Graphene’s potential, evident in so many other areas, has, shall we say, been brought to light once again. The use of this nanomaterial makes for lighting options that are cheaper, safer and more efficient than those that came before, and very well might serve as a beacon to the future.