Luminescence tuning and exciton dynamics of Mn-doped CsPbCl₃nanocrystals

Abstract

Mn-Doped perovskite nanocrystals (NCs) are a new class of materials offering exciting opportunities to control over their optical and magnetic properties. Herein, we report a series of Mn-doped CsPbCl NCs exhibiting a tunable Mn photoluminescence (PL) band with a PL peak wavelength pushed up to 625 nm and tuned over a range of 40 nm, the largest achieved so far, by only varying the Mn content. The X-band EPR data and Mn PL decay behaviour of the NCs reveal that the exchange interaction between Mn ions is mainly responsible for a large shift of the Mn PL band. Ultrafast pump-probe measurements show that exciton-dopant energy transfer in these NCs is slower (∼50-100 ps) than trapping of the carriers (∼8-10 ps) in the host lattice. The large PL tuning reported here along with the insights into the mechanism of tuning and carrier dynamics are expected to boost the potential of Mn-doped CsPbCl NCs in light-powered devices.

Lead‐Free Semiconductors: Soft Chemistry, Dimensionality Control, and Manganese‐Doping of Germanium Halide Perovskites

“…Interestingly, a similar observation is observed for Mn 2+ ‐doped CsPbCl 3 at low temperatures that induce phase transitions to lower symmetry structures . The hyperfine splitting constants of 90–96 G are larger than the 86–87 G values recently observed for Mn 2+ ‐doped CsPbCl 3 ,,,,,,,which is consistent with the higher lattice ionicity of germanium halide perovskites…”

“…[80] Interestingly, a similar observation is observed for Mn 2 + -doped CsPbCl 3 at low temperatures that induce phase transitions to lower symmetry structures. [81] The hyperfine splitting constants of 90-96 G are larger than the 86-87 G values recently observed for Mn 2 + -doped CsPbCl 3 , [60,63,64,66,78,81,82] which is consistent with the higher lattice ionicity of germanium halide perovskites. [83] Considering Vegard's Law, [84,85] we estimate we can incorporate Mn 2 + ions up to 29% in bulk and up to 16% in nanocrystalline samples ( Figure 5).…”

“…Recently, significant research focused on doping metal halide perovskites with transition or main group metals . Doping with up to 46% Mn 2+ is currently possible, leading to modified magnetic and optical properties . Mn 2+ ‐doping enhances stability, increases quantum yield to 60%, and results in long exciton lifetimes ,.…”

“…[56][57][58] Doping with up to 46% Mn 2 + is currently possible, [59] leading to modified magnetic and optical properties. [60][61][62][63][64] Mn 2 + -doping enhances stability, [65][66][67] increases quantum yield to 60%, [68] and results in long exciton lifetimes. [69,70] These enhanced properties are useful for LEDs [67,71] and solar cell downconverters.…”

Single-crystalline perovskite wafers with a Cr blocking layer for broad and stable light detection in a harsh environment

“…1b, which provide evidence the as-grown MAPbI 3 wafer was tetrahedral phase, and shown the (112) facets. 41,42 By scanning (112) facets, diffractions corresponded to {112} crystal planes appearance. It should be mentioned that the synchronized appearance of {112} crystal planes was attributed to their adjacent 2q value (the difference is $0.1 ).…”