Bleifreie Halogenid‐Perowskit‐Nanokristalle: Kristallstrukturen, Synthese, Stabilitäten und optische Eigenschaften

Abstract

In den letzten Jahren gab es rasante Fortschritte bei der Synthese von Bleihalogenid‐Perowskit‐Nanokristallen (NCs) für den Einsatz in Solarzellen, Leuchtdioden, Lasern und Photodetektoren. Sie besitzen eine Reihe faszinierender optischer, excitonischer und Ladungstransporteigenschaften, einschließlich hervorragender Photolumineszenz‐Quantenausbeuten (PLQY) und abstimmbaren optischen Bandlücken. Die notwendige Verwendung von Blei, einem toxischen Element, gibt jedoch Anlass zu ernsthafter Besorgnis über die zukünftige kommerzielle Entwicklung. Um das Problem der Toxizität zu lösen, wurden in jüngster Zeit intensive Forschungsarbeiten zur Entwicklung bleifreier Halogenid‐Perowskit(LFHP)‐NCs durchgeführt. In diesem Aufsatz geben wir einen Überblick über die derzeit erforschten LFHP‐NCs mit den Schwerpunkten Kristallstruktur, Synthese, optische Eigenschaften und Umgebungsstabilität (z. B. UV‐, Wärme‐ und Feuchtigkeitsbeständigkeit). Darüber hinaus werden Strategien zur Verbesserung der optischen Eigenschaften und Stabilitäten von LFHP‐NCs sowie deren neueste Anwendungen diskutiert.

Enhanced Thermal Stability of Halide Perovskite CsPbX3 Nanocrystals by a Facile TPU Encapsulation

“…[25,26] However, the applications of CsPbX 3 (X = Br, I, Cl) NCs have been severely hindered by the issue of the stability, mainly derived from thermal degradation and atmospheric moisture. [27][28][29][30] To www.advopticalmat.de elasticity, which paves the way for development and commercialization of the perovskite materials. Our results demonstrate that the encapsulation strategy plays an indispensable role in future applications of perovskite.…”

Lead‐Free Sodium–Indium Double Perovskite Nanocrystals through Doping Silver Cations for Bright Yellow Emission

“…Therefore,replacement of Pb with less toxic or non-toxic elements becomes an effective solution and has been investigated. [8][9][10] Isovalent substitution became aw ay to obtain lead-free halide perovskites NCs CsBX 3 (B = Sn 2+ ,G e 2+ ). [11,12] Unfortunately,t he Sn 2+ and Ge 2+ ions are extremely instable and oxidized easily to Sn 4+ and Ge 4+ ,r espectively.H eterovalent substitution can form lead-free perovskites NCs:f irstly,s ubstituting three Pb 2+ cations with two trivalent B 3+ cations A 3 B 2 X 9 (A = Cs,R b; B = Sb,B i) ; [13][14][15][16] secondly,s ubstituting two Pb 2+ cations with aq uadrivalent B 4+ cation Cs 2 BX 6 (B = Sn, Pd); [17,18] thirdly, substituting two Pb 2+ cations with am onovalent B + and at rivalent B' 3+ cations Cs 2 BB'X 6 (B = Ag, Na;B ' = Bi, Sb, In).…”

Stable Lead‐Free Tin Halide Perovskite with Operational Stability >1200 h by Suppressing Tin(II) Oxidation

“…More importantly, the stabilities problem that restricted the development of Pb‐based perovskite have also been greatly improved by encapsulation, extending from the initial life of a few hours to hundreds of hours [9–12] . However, the highly intrinsic toxicity of heavy metal Pb causes a potential threat to the environment and human health, which seriously hinders their practical application [13, 14] . Therefore, there is considerable interest in trying to replace Pb with non‐toxic or less toxic elements, for example, isovalent substitution (Sn 2+ , Ge 2+ ) or heterovalent substitution (Bi 3+ , Ag + ), to form lead‐free perovskites [13, 14] .…”

“…However, the highly intrinsic toxicity of heavy metal Pb causes a potential threat to the environment and human health, which seriously hinders their practical application [13, 14] . Therefore, there is considerable interest in trying to replace Pb with non‐toxic or less toxic elements, for example, isovalent substitution (Sn 2+ , Ge 2+ ) or heterovalent substitution (Bi 3+ , Ag + ), to form lead‐free perovskites [13, 14] . Among these elements, tin (Sn 2+ ) seems to be the most promising alternative for lead (Pb 2+ ), because it is in the same group of the periodic table with lead and has the most similar electronic properties [15, 16] …”