摘要： Cesium lead halide nanocrystals (CsPbX3 NCs) are newcomer inorganic light sources covering the entire visible spectral range and exhibiting near-unity efficiencies. While the last years have seen rapid progress in green- and red-electroluminescence from CsPbX3 NCs, the development of blue counterparts remained rather stagnant. Controlling the surface state of CsPbX3 NCs had proven to be a major factor governing the efficiency of the charge injection and for diminishing the density of traps. Although didodecyldimethylammonium halides (DDAX, X=Br, Cl) had been known to improve the luminescence of CsPbX3 NCs when applied post-synthetically, they had not been used as a sole long-chain ammonium ligand directly in the synthesis of these NCs. Herein we report a facile, direct synthesis of DDAX-stabilized CsPbX3 NCs. We then demonstrate blue and green light-emitting diodes, characterized by the electroluminescence at 463-515 nm and external quantum efficiencies of 9.80% for green, 4.96% for sky-blue and 1.03% for deep-blue spectral regions.