Metal halide perovskite light-emitting diodes(LEDs)have achieved great progress in recent years.However,bright and spectrally stable blue perovskite LED remains a significant challenge.Three-dimensional mixed-halide p...Metal halide perovskite light-emitting diodes(LEDs)have achieved great progress in recent years.However,bright and spectrally stable blue perovskite LED remains a significant challenge.Three-dimensional mixed-halide perovskites have potential to achieve high brightness electroluminescence,but their emission spectra are unstable as a result of halide phase separation.Here,we reveal that there is already heterogeneous distribution of halides in the as-deposited perovskite films,which can trace back to the nonuniform mixture of halides in the precursors.By simply introducing cationic surfactants to improve the homogeneity of the halides in the precursor solution,we can overcome the phase segregation issue and obtain spectrally stable single-phase blueemitting perovskites.We demonstrate efficient blue perovskite LEDs with high brightness,e.g.,luminous efficacy of 4.7,2.9,and 0.4 lmW^(-1) and luminance of over 37,000,9,300,and 1,300 cdm^(-2) for sky blue,blue,and deep blue with Commission Internationale de l’Eclairage(CIE)coordinates of(0.068,0.268),(0.091,0.165),and(0.129,0.061),respectively,suggesting real promise of perovskites for LED applications.展开更多
基金This work is financially supported by the Major Research Plan of the National Natural Science Foundation of China(91733302)the National Natural Science Foundation of China(61875084,61922041,61961160733,61722403,11674121,and 51703094)+6 种基金the National Science Fund for Distinguished Young Scholars(61725502)the Natural Science Foundation of Jiangsu Province,China(BK20180085 and BK20170991)the Major Program of Natural Science Research of Jiangsu Higher Education Institutions of China(19KJA520004)the Jilin Province Science and Technology Development Program(20190201016JC)the Synergetic Innovation Center for Organic Electronics and Information Displays.N.W.is a Marie Skłodowska-Curie Fellow(841454)C.L.’s studies are supported by the EPSRC under EP/R025193/1Calculations were performed in part at the High Performance Computing Center of Jilin University.
文摘Metal halide perovskite light-emitting diodes(LEDs)have achieved great progress in recent years.However,bright and spectrally stable blue perovskite LED remains a significant challenge.Three-dimensional mixed-halide perovskites have potential to achieve high brightness electroluminescence,but their emission spectra are unstable as a result of halide phase separation.Here,we reveal that there is already heterogeneous distribution of halides in the as-deposited perovskite films,which can trace back to the nonuniform mixture of halides in the precursors.By simply introducing cationic surfactants to improve the homogeneity of the halides in the precursor solution,we can overcome the phase segregation issue and obtain spectrally stable single-phase blueemitting perovskites.We demonstrate efficient blue perovskite LEDs with high brightness,e.g.,luminous efficacy of 4.7,2.9,and 0.4 lmW^(-1) and luminance of over 37,000,9,300,and 1,300 cdm^(-2) for sky blue,blue,and deep blue with Commission Internationale de l’Eclairage(CIE)coordinates of(0.068,0.268),(0.091,0.165),and(0.129,0.061),respectively,suggesting real promise of perovskites for LED applications.
