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  • Synthesis of lead-free Cs 4 (Cd 1−x Mn x )Bi 2 Cl 12 (0 ≤ x ≤ 1) layered double perovskite nanocrystals with controlled Mn–Mn coupling interaction
Title: Synthesis of lead-free Cs 4 (Cd 1−x Mn x )Bi 2 Cl 12 (0 ≤ x ≤ 1) layered double perovskite nanocrystals with controlled Mn–Mn coupling interaction
Lead-free perovskites and their analogues have been extensively studied as a class of next-generation luminescent and optoelectronic materials. Herein, we report the synthesis of new colloidal Cs 4 M( ii )Bi 2 Cl 12 (M( ii ) = Cd, Mn) nanocrystals (NCs) with unique luminescence properties. The obtained Cs 4 M( ii )Bi 2 Cl 12 NCs show a layered double perovskite (LDP) crystal structure with good particle stability. Density functional theory calculations show that both samples exhibit a wide, direct bandgap feature. Remarkably, the strong Mn–Mn coupling effect of the Cs 4 M( ii )Bi 2 Cl 12 NCs results in an ultra-short Mn photoluminescence (PL) decay lifetime of around 10 μs, around two orders of magnitude faster than commonly observed Mn 2+ dopant emission in NCs. Diluting the Mn 2+ ion concentration through forming Cs 4 (Cd 1−x Mn x )Bi 2 Cl 12 (0 < x < 1) alloyed LDP NCs leads to prolonged PL lifetimes and enhanced PL quantum yields. Our study provides the first synthetic example of Bi-based LDP colloidal NCs with potential for serving as a new category of stable lead-free perovskite-type materials for various applications.  more » « less
Award ID(s):
1943930
NSF-PAR ID:
10213793
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
12
Issue:
45
ISSN:
2040-3364
Page Range / eLocation ID:
23191 to 23199
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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