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  • Ligand-mediated synthesis of chemically tailored two-dimensional all-inorganic perovskite nanoplatelets under ambient conditions
Title: Ligand-mediated synthesis of chemically tailored two-dimensional all-inorganic perovskite nanoplatelets under ambient conditions
All-inorganic halide perovskite nanocrystals (NCs) offer impressive optoelectronic properties for light harvesting, energy conversion, and photoredox applications, with two-dimensional (2D) perovskite NCs further increasing these prospects due to their improved photoluminescence (PL) tuneability, impressive color purity, high in-plane charge transport, and large lateral dimensions which is advantageous for device integration. However, the synthesis of 2D perovskites is still challenging, especially toward large-scale applications. In this study, through the control of surface ligand composition and concentration of a mixture of short (octanoic acid and octylamine, 8-carbon chain) and long (oleic acid and oleylamine, 18-carbon chain) ligands, we have developed an extremely facile ligand-mediated synthesis of 2D CsPbX 3 (X = Cl, Br, or mixture thereof) nanoplatelets (NPLs) at room temperature in an open vessel. In addition, the developed method is highly versatile and can be applied to synthesize Mn-doped CsPbX 3 NPLs, showing a systematic increase in the total PL quantum yield (QY) and the Mn-dopant emission around 600 nm with increasing Mn and Cl concentrations. The reaction occurs in toluene by the introduction of CsX, PbX 2 , and MnX 2 precursors under ambient conditions, which requires no harsh acids, avoids excessive lead waste, little thermal energy input, and is potentially scalable toward industrial applications.  more » « less
Award ID(s):
1944978
PAR ID:
10312853
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
9
Issue:
40
ISSN:
2050-7526
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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