UK researchers create LEDs engineered at an atomic level
Researchers at the Universities of Manchester and Sheffield in the UK have shown that new 2D materials can be stacked into complex but carefully designed sequences to create flexible, see-through, and more efficient electronic devices. The team, led by Nobel Laureate Kostya Novoselov, made the breakthrough by creating LEDs engineered in this way .
The new research shows that graphene and related 2D materials including MoS2, insulating hexagonal BN and various other semiconducting monolayers made from transition metal dichalcogenides (TMDCs) could be used to create LEDs for the next-generation of mobile phones, tablets and televisions to make them incredibly thin, flexible, durable and even semi-transparent.
The LED device developed in this way emits light from across its whole surface. Being only 10-40 atoms thick, these new components can form the basis for the first generation of semi-transparent smart devices, according to the team.
Freddie Withers, Royal Academy of Engineering Research Fellow at the University of Manchester, who led the production of the devices, said: "As our new type of LED's only consist of a few atomic layers of 2D materials they are flexible and transparent. We envisage a new generation of optoelectronic devices to stem from this work, from simple transparent lighting and lasers and to more complex applications."
Explaining the creation of the LED device Kostya Novoselov said: "By preparing the heterostructures on elastic and transparent substrates, we show that they can provide the basis for flexible and semi-transparent electronics.
"The range of functionalities for the demonstrated heterostructures is expected to grow further on increasing the number of available 2D crystals and improving their electronic quality."
Alexander Tartakovskii, from the University of Sheffield added: "The novel LED structures are robust and show no significant change in performance over many weeks of measurements.
"Despite the early days in the raw materials manufacture, the quantum efficiency (photons emitted per electron injected) is already comparable to organic LEDs."
'Light-emitting diodes by band-structure engineering in van derWaals heterostructures' by F.Withers et al, Nature Materials (2015) doi:10.1038/nmat4205
