Efficient and Bright Pure-Blue All-Inorganic Perovskite Light-Emitting Diodes from an Ecofriendly Alloy

and an EQE of 1.43%. The device yields a record radiance among the most efficient PeLEDs at 467 nm. In addition, the resultant PeLEDs displayed exceptional spectral stability during the electrical bias operation. Our work provides a promising avenue to develop environmentally friendly perovskite materials for efficient and spectrally stable pure-blue PeLEDs and beyond.