Perovskite light-emitting diodes ( LEDs ) have shown great potential in next-generation display technologies due to their excellent light-emitting properties and low cost . Despite substantial progress in green and red light -emitting devices, the development of high-efficiency blue perovskite LEDs has been slower.
Based on this, Professor Cui Linsong of the University of Science and Technology of China and Samuel D. Stranks of the University of Cambridge reported high-efficiency blue perovskite LEDs based on mixed two -dimensional and three-dimensional perovskites and a multifunctional ionic additive that enables the reduction of dimensionality. , non-radiative recombination channels and spectral stability control become possible. A series of devices confirmed that they emit high-efficiency electroluminescence from the mixed bromide / chloride quasi-three-dimensional region, with external quantum efficiencies up to 21.4% (brightness 22 cd/m² , emission peak wavelength 483 nm ), 13.2 % (brightness is 2.0 cd/m² , emission peak wavelength is 474 nm ) and 7.3% (brightness is 6 cd/m² , emission peak wavelength is 464 nm ).
Compared to control LEDs , the operating stability of these devices is almost 30 times improved , with a half-life of 129 minutes at an initial brightness of 100 cd/m² . The performance of these blue-emitting perovskite LEDs is close to that of state-of-the-art blue-emitting organic LEDs and inorganic quantum dot LEDs , and provides a new way to design multifunctional molecules to enhance the performance of perovskite optoelectronic devices.