Epitaxial Growth of Blue-Emitting CsPbBr₃ Nanocrystals on a Pb-Doped LDH Matrix and Application in White LEDs

Halide perovskite quantum dots (QDs) have demonstrated outstanding performance in light-emitting applications. However, the performance of blue perovskite QDs lags far behind that of their red and green counterparts, especially those with color coordinates approaching (0.131, 0.046), which meet the Rec. 2020 specification for blue emitters. This article employs a hot injection method to epitaxially grow CsPbBr₃ nanocrystals (NCs) on the surface of Pb-doped Ni-Co LDH. The doping of Pb in the LDH provides epitaxial anchoring sites for the growth of the perovskite nanocrystals. The resulting CsPbBr₃@Pb-LDH composite exhibits stable blue emission characteristics. The photoluminescence quantum yield (PLQY) increased from 37.65% for CsPbBr₃ to 74.26%, accompanied by an extended fluorescence lifetime (6.42 ns). It retained 48% of its initial photoluminescence (PL) intensity after continuous irradiation for 5 h. We utilized these NCs as a color conversion layer to develop efficient white light-emitting diodes (WLEDs). The resulting pure white emission exhibited color coordinates of (0.312, 0.327). Our findings offer a valuable alternative material for applications in solid-state lighting and displays.