KxCs1−xPbBr3 NCs glasses possessing super optical properties and stability for white light emitting diodes

Abstract

CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) glasses formed utilizing conventional melt-quenching with a subsequent heat-treatment method demonstrate excellent performance and can resist temperature and light irradiation; further, CsPbX3 NCs glasses have improved stability in air and water when compared to traditional way. Nevertheless, one of the fatal disadvantages of CsPbX3 NCs glasses are their low photoluminescence quantum yields (PLQY). Here, we demonstrate a new avenue that K+ ions doped CsPbBr3 NCs glasses (K-CPB NCs glasses) systems utilizing KxCs1−xPbBr3 (x = 0, 0.2, 0.4, 0.6, 0.8, 1) NCs glasses, and we surprisingly find that K0.6Cs0.4PbBr3 NCs glass reaches the highest PLQY of 62% when the molar ratio of K+/Cs+ = 0.6/0.4. Meanwhile, in comparative experiments, we have noticed that K0.6Cs0.4PbBr3 NCs glass has better water resistance and thermal stability than CsPbBr3 NCs glasses what we had before. K-CPB NCs glasses has a significantly improved applications scope for cesium lead halide perovskite in the field of photoelectricity, such as solar cells and perovskite light-emitting diodes (PeLEDs). In addition, we have successfully fabricated the pure phase of KPbBr3 NCs glass and its existence has been proven via a series of representational means, consequently, this research opens the door for the further study of perovskite materials. Fortunately, K-CPB NCs glasses perform better in optical third-order nonlinearity, and we believe these findings will promote its applications in nonlinear optoelectronic devices. Ultimately, white LEDs (WLEDs) has been successfully equipped with K0.6Cs0.4PbBr3 NCs glass, which presents excellent optical parameters.