Stabilization of Lead–Tin-Alloyed Inorganic–Organic Halide Perovskite Quantum Dots

Abstract

Recently, lead−tin-based alloyed halide perovskite quantum dots (QDs) with improved stability and less toxicity have been introduced. However, the perovskite QDs containing tin are still unstable and exhibit low photoluminescence quantum yields (PLQYs), owing to the presence of defects in the alloyed system. Here, we have attempted to introduce sulfur anions (S 2− ) into the host lattice (MAPb 0.75 Sn 0.25 Br 3 ) as a promising route to stable alloyed perovskite QDs with improved stability and PLQY. In this study, we used elemental sulfur as a sulfur precursor. The successful incorporation of sulfur anions into the host lattice resulted in a highly improved PLQY (>75% at room temperature), which is believed to be due to a reduction in the defect-related non-radiative recombination centers present in the host lattice. Furthermore, we found that the emission property could be tuned between the bright green and cyanbluish regions without compromising on color quality. This work invigorates the perovskite research community to prepare stable, bright, and color-tunable alloyed inorganic−organic perovskite QDs without compromising on their phases and color quality, which can lead to considerable advances in display technology.

Experimental and Theoretical Investigation of the Structural and Opto‐electronic Properties of Fe‐Doped Lead‐Free Cs2AgBiCl6 Double Perovskite

“…We examined the photophysical properties and determined the Urbach energy ( E u ) of Fe‐doped double perovskite materials. It shows structural disorders, effects of impurities, and electron‐phonon interactions in the absorption phenomenon [51] …”

The Role of Surface Termination in Halide Perovskites for Efficient Photocatalytic Synthesis

“…The broadening of the emission spectra of the aged samples comes from the hydration and/or hydrogen bonding interactions between water molecules, organic cation (MA + ) and halide ions, leading to the formation of new surface defects. A blue‐shift of 16 nm for PL peak of MAPbI 3 ‐A1 also suggests the formation of additional defects after ageing …”

Synthesis of two-dimensional phenylethylamine tin–lead halide perovskites with bandgap bending behavior

“…47,50,51 However, it was remarkable that the absorption spectra of PEA 2 Sn x Pb 1Àx Br 4 had a distinctive shi different from common materials. 52,53 Nevertheless, the bandgap change of PEA 2 Sn x Pb 1Àx Br 4 exhibited special bending along with the content changes as shown in Fig. 2.…”