Interfacial Manganese‐Doping in CsPbBr₃ Nanoplatelets by Employing a Molecular Shuttle

Abstract

Mn‐doping in cesium lead halide perovskite nanoplatelets (NPls) is of particular importance where strong quantum confinement plays a significant role towards the exciton–dopant coupling. In this work, we report an immiscible bi‐phasic strategy for post‐synthetic Mn‐doping of CsPbX3 (X=Br, Cl) NPls. A systematic study shows that electron‐donating oleylamine acts as a shuttle ligand to transport MnX2 through the water–hexane interface and deliver it to the NPls. The halide anion also plays an essential role in maintaining an appropriate radius of Mn2+ and thus fulfilling the octahedral factor required for the formation of perovskite crystals. By varying the thickness of parent NPls, we can tune the dopant incorporation and, consequently, the exciton‐to‐dopant energy transfer process in doped NPls. Time‐resolved optical measurements offer a detailed insight into the exciton‐to‐dopant energy transfer process. This new approach for post‐synthetic cation doping paves a way towards exploring the cation exchange process in several other halide perovskites at the polar–nonpolar interface.

Optimizing optical properties of hybrid core/shell perovskite nanocrystals

“…Over the past several years, various methods have been developed to improve the optical properties of semiconductor NCs, including surface chemistry, 13,14 core–shell nanostructures, 15,16 doping, 17 and alloying. 18,19 Among the abovementioned methods, the design of core–shell nanostructures has been proven to be an efficient method that can improve the optical properties of semiconductor NCs.…”

Efficient Interfacial Synthesis Strategy for Perovskite CsPbBr3 Nanorods in the Biphase Solution

“…The interface between the water and hexane acts as a semi permeable membrane which provides the space for Pb 2+ to insert into CsBr NCs. [ 38 ] Pb 2+ cations act as the binder to connect the NCs formed into the NRs. In the experiment, the postsynthetic CB2‐5‐10000 NCs were mixed with the PbAc 2 /H 2 O solution in different concentrations and transformed into CsPbBr 3 NRs.…”

“…The proposed interfacial synthesis method offers the possibility for efficient synthesis; however, this transformation has quite obvious limitations and does not suitable for other types of perovskite or other kinds of synthetic routes. Very recently, our group [ 38 ] proposed a postsynthetic interfacial doping strategy that the polar solvent water allowed for a large amount of dissolved MnX 2 salts for doping. In such a two phases system, water could be intrinsically separated from the hexane phase, which helps maintain the product's quality and stability.…”

“…The proposed interfacial synthesis method offers the possibility for efficient synthesis; however, this transformation has quite obvious limitations and does not suitable for other types of perovskite or other kinds of synthetic routes. Very recently, our group [38] proposed a postsynthetic interfacial doping strategy that the polar solvent water allowed for a 1D APbX 3 (A = Cs, MA, FA, X = Cl, Br, I) nanorods (NRs) show potential for the future integrated optoelectronic devices as the ideal building blocks due to their outstanding optoelectronic performances. However, there is still a lack of high-efficiency controllable strategies to synthesize CsPbX 3 NRs.…”

Enhanced Performance of Two-Photon Excited Amplified Spontaneous Emission by Cd-Alloyed CsPbBr3 Nanocrystals

“…Chen treated the as-synthesized CsPbCl 3 perovskite NCs with CdCl 2 and found that their PLQYs increased from 0.9% to 60.5% . Considering the great progress in the synthesis of B-site alloying and doping perovskite NCs, an in-depth understanding of their photophysical properties will be essential for relevant applications.…”