Highly Tunable Emission by Halide Engineering in Lead-Free Perovskite-Derivative Nanocrystals: The Cs2SnX6 (X = Cl, Br, Br/I, I) System

Alessandro Veronese; Maddalena Patrini; Daniele Bajoni; Carlo Ciarrocchi; Paolo Quadrelli; Lorenzo Malavasi

doi:10.3389/fchem.2020.00035

Highly Tunable Emission by Halide Engineering in Lead-Free Perovskite-Derivative Nanocrystals: The Cs₂SnX₆ (X = Cl, Br, Br/I, I) System

Front Chem. 2020 Jan 31:8:35. doi: 10.3389/fchem.2020.00035. eCollection 2020.

Authors

Alessandro Veronese¹, Maddalena Patrini¹, Daniele Bajoni², Carlo Ciarrocchi³, Paolo Quadrelli³, Lorenzo Malavasi³

Affiliations

¹ Department of Physics and CNISM, University of Pavia, Pavia, Italy.
² Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy.
³ Department of Chemistry and INSTM, University of Pavia, Pavia, Italy.

Abstract

Nanocrystals of Cs₂SnX₆ (X = Cl, Br, Br_0.5I_0.5, and I) have been prepared by a simple, optimized, hot-injection method, reporting for the first time the synthesis of Cs₂SnCl₆, Cs₂SnBr₆, and mixed Cs₂Sn(I_0.5Br_0.5)₆ nanocrystalline samples. They all show a cubic crystal structure with a linear scaling of lattice parameter by changing the halide size. The prepared nanocrystals have spherical shape with average size from 3 to 6 nm depending on the nature of the halide and span an emission range from 444 nm (Cs₂SnCl₆) to 790 nm (Cs₂SnI₆) with a further modulation provided by mixed Br/I systems.

Keywords: emission; lead-free; nanocrystal; nanocrystal (NC); perovskite; spectroscopy.