Discovering a New Class of Materials for Making LEDs
July 20, 2015 | UCLA NewsroomEstimated reading time: 1 minute
Over the last decade, advances in the technology of light-emitting diodes, or LEDs, have helped to improve the performance of devices ranging from television and computer screens to flashlights. As the uses for LEDs expand, scientists continue to look for ways to increase their efficiency while simplifying how they are manufactured.
A new study by researchers from the California NanoSystems Institute at UCLA is the first demonstration of electroluminescence from multilayer molybdenum disulfide, or MoS2, a discovery that could lead to a new class of materials for making LEDs. The study, led by Xianfeng Duan, professor of chemistry and biochemistry, was published in the journal Nature Communications on July 1, 2015.
In its single-layer form, molybdenum disulfide is optically active, meaning that it emits light when electric current is run through it or when it is shot with a nondestructive laser. Multilayer molybdenum disulfide, by contrast, is easier and less expensive to produce, but it is not normally luminescent. In the new study, Duan and first author Dehui Li, a postdoctoral scholar in Duan’s lab, created the first multilayer molybdenum disulfide device that shows strong luminescence when electrical current is passed through it.
“We were trying to make a vertically stacked light-emitting device based on monolayer MoS2, but it was difficult to get the efficiency as high as we wanted,” Duan said. “On the other hand, it was rather surprising for us to discover that similar vertical devices made of multilayer MoS2 somehow showed very strong electroluminescence, which was completely unexpected since the multilayer MoS2 is generally believed to be optically inactive. So we followed this new lead to investigate the underlying mechanism and the potential of multilayer MoS2 in light-emitting devices.”
Duan and his team used a technique called electric field-induced enhancement, which relocates the electrons from a dark state to a luminescent state, thereby increasing the material’s ability to convert electrons into light particles, or photons. With this technique, the multilayer MoS2 semiconductors are at least as efficient as monolayer ones.
Duan’s team is currently moving forward to apply this approach to similar materials, including tungsten diselenide, molybdenum diselenide and tungsten disulphide, with the goal of helping to create a new generation of light-emitting devices from two-dimensional layered materials, which are less expensive and easier to use in manufacturing.
Suggested Items
2024 Apple iPad Pro Estimated to Ship Between 4.5 to 5 Million Units
05/08/2024 | TrendForceApple’s recent product launch in May introduced a lineup of new tablets featuring advanced AMOLED screens. Notably, the Pro version boasts a dual-layer tandem structure designed to address the longstanding challenges of screen burn-in and lifespan that are common with AMOLED displays.
AIM Solder Signs Shinil Fl Ltd. as New Distributor for Korea
05/08/2024 | AIM SolderAIM Solder, a leading global manufacturer of solder assembly materials for the electronics industry, is pleased to announce a new distribution partnership with Shinil Fl Ltd., a prominent supplier of technological solutions in the SMT and semiconductor sectors.
IDTechEx Discusses Low-Loss Materials: The Enabler of Future Connected Vehicles?
05/06/2024 | IDTechExFuture connected vehicles will offer future drivers a safer, smoother, and more convenient driving experience. Not only will drivers get access to more navigation and entertainment options, but they will also gain access to safety technologies that will potentially reduce accidents, improve congestion, and reduce emissions globally by allowing vehicle safety systems to communicate with each other and with city traffic infrastructure.
LQDX Divests Aluminum Soldering Business - Mina™ - to Taiyo America Inc.
05/02/2024 | PRNewswireLQDX, formerly known as Averatek Corp., developer of high-performance materials for advanced semiconductor manufacturing, today announced that it has divested its aluminum soldering business – known as MinaTM – to Taiyo America Inc., a global market leader in advanced electronic materials.
Indium Corporation Expert to Present on Pb-Free Solder for Die-Attach in Discrete Power Applications
04/30/2024 | Indium CorporationIndium Corporation Product Manager – Semiconductor Dean Payne will present at the Advanced Packaging for Power Electronics conference, hosted by IMAPS, held May 8-9 in Woburn, Massachusetts, USA.