Enhanced Stability and Luminous Performance for Structured Mn‐Doped CsPbCl₃ Quantum Dots

Abstract

To improve the photoluminescence quantum yield (PL QY) and the environmental stability of the CsPbCl 3 quantum dots (QDs), the Mn doping strategy has been applied first. The substitute of Mn 2 + can reduce the toxicity of the lead element firstly, and then slightly enhance the stability of QDs. Increasing the nominal content of Mn, the longtime duration of the intrinsic excitation peak is significantly improved; and at a higher nominal content, a wide red emission by the d-d transition of Mn 2 + is introduced, the overall PL QY of CsPbCl 3 QDs increases to 54.32 %. Secondly, to further prevent the penetration of oxygen and water, the Mn-doped CsPbCl 3 @SiO 2 nano-composite with a physical coating shell was synthesized by the hydrolysis of aminopropyltriethoxysilane. The investigation on the PL spectrum within hours shows that the relative peak intensity maintains 74 % of the initial intensity and the shift of peak position is also inhibited. Finally, the nano-composite materials were fabricated into white light-emitting devices (WLED), under the illumination of a commercial GaN chip, the device shows a good Commission Internationale de lEclairage (CIE) color coordination of (0.31,0.35). As a result, the obtained Mn-doped CsPbCl 3 @SiO 2 QDs have excellent optical properties and good stability under aqueous and polar solvent environments. Therefore, this doping and coating method could pave the way for future applications in illumination and display fields.

Enhanced energy transfer by Sb ion doping for efficient CsPbCl3:Mn2+perovskite nanocrystals and light emitting diodes

“…11,12 For example, the typical transition metal Mn 2+ has been incorporated into perovskite NCs, such as CsPbCl 3 , to achieve new optical properties, which shows a narrow violet exciton emission of perovskite NCs and a stable broad orange emission ( 4 T 1 -6 A 1 d-d transition of Mn 2+ ), 13 originating from the energy transfer from CsPbCl 3 NCs to Mn 2+ . [14][15][16][17][18] The emission of Mn 2+ is detuned from the absorption of the CsPbCl 3 NC host, which effectively prevents the reabsorption process and facilitates application in many fields, 19,20 e.g., WLEDs, 21,22 solar cells, and so on. [23][24][25] However, the energy transfer efficiency from the CsPbCl 3 NC host to Mn 2+ is lower by several orders of magnitude, compared to that of Mn 2+ doped II-VI quantum dots.…”

“…14–18 The emission of Mn 2+ is detuned from the absorption of the CsPbCl 3 NC host, which effectively prevents the reabsorption process and facilitates application in many fields, 19,20 e.g. , WLEDs, 21,22 solar cells, and so on. 23–25 However, the energy transfer efficiency from the CsPbCl 3 NC host to Mn 2+ is lower by several orders of magnitude, compared to that of Mn 2+ doped II–VI quantum dots.…”