(Press-News.org) Energy-efficient light-emitting diodes (LEDs) have been used in our everyday life for many decades. But the quest for better LEDs, offering both lower costs and brighter colours, has recently drawn scientists to a material called perovskite. A recent joint-research project co-led by the scientist from City University of Hong Kong (CityU) has now developed a 2D perovskite material for the most efficient LEDs.
From household lighting to mobile phone displays, from pinpoint lighting needed for endoscopy procedures to light source to grow vegetables in Space, LEDs are everywhere. Yet current high-quality LEDs still need to be processed at high temperatures and using elaborated deposition technologies -- which make their production cost expensive.
Scientists have recently realised that metal halide perovskites - semiconductor materials with the same structure as calcium titanate mineral, but with another elemental composition - are extremely promising candidates for next-generation LEDs. These perovskites can be processed into LEDs from solution at room temperature, thus largely reducing their production cost. Yet, the electro-luminescence performance of perovskites in LEDs still has room for improvement.
Led by Professor Andrey Rogach, Chair Professor at the Department of Materials Science and Engineering at CityU, and his collaborator Professor Yang Xuyong from Shanghai University, the team has found a kind of dimmer switch: they could turn one light emission from perovskites to a brighter level!
They worked with two-dimensional (2D) perovskites (also known as Ruddlesden-Popper perovskites) and succeeded to realise very efficient and bright LEDs, with best-reported performance on both current efficiency and external quantum efficiency for devices based on this kind of perovskites. This work has now put the perovskite LEDs close on the heels of current commercial display technologies, such as organic LEDs.
Their findings were published in the scientific journal Nature Communications, titled " END
Producing highly efficient LEDs based on 2D perovskite films
2021-03-10
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