Highly Luminescent and Stable CsPbI₃ Perovskite Nanocrystals with Sodium Dodecyl Sulfate Ligand Passivation for Red-Light-Emitting Diodes

Abstract

CsPbI3 perovskite nanocrystals (NCs) have recently emerged as promising materials for optoelectronic devices because of their superior properties. However, the poor stability of the CsPbI3 NCs induced by easy ligand desorption represents a key issue limiting their practical applications. Herein, we report stable and highly luminescent black-phase CsPbI3 NCs passivated by novel ligands of sodium dodecyl sulfate (SDS). Theoretical calculation results reveal a stronger adsorption energy of SDS molecules at the CsPbI3 surface than that of commonly used oleic acid. As a result, the defect formation caused by the ligand loss during the purification process is greatly suppressed. The optimized SDS–CsPbI3 NCs exhibit significantly reduced surface defects, much enhanced stability, and superior photoluminescence efficiency. The red perovskite light-emitting diodes based on the SDS–CsPbI3 NCs demonstrate an external quantum efficiency of 8.4%, which shows a 4-fold improvement compared to the devices based on the oleic acid-modified CsPbI3 NCs.

Strong violet emission from ultra-stable strontium-doped CsPbCl3 superlattices

“…Recently, metal-halide perovskite nanostructures, in particular solution-processable caesium lead halide PQDs, as an emergent branch of semiconducting QDs, have received an enormous level of interest due to their cost-effective synthesis and variety of fascinating optoelectronic properties, 1–4 such as a narrow full width at half-maximum, high PLQYs, and composition- and size-dependent emission wavelengths, which endow them with great application prospects not only in the basic research of nanoscience but also in various optoelectronic devices, such as light-emitting diodes, solar cells, and detectors. 5–7 Interestingly, although high PLQYs (80–95%) in the green-red region have been reported for PQDs, violet-emitting CsPbCl 3 PQDs still suffer from low PLQYs.…”

A Reparameterized Density Functional Tight-Binding Method for Engineering phase-stable CsPbX\textsubscript{3} Perovskites

“…[19][20][21] Most computational studies of MHPs are performed using density functional theory (DFT). [22][23][24] However, due the high computational costs of DFT it is unsuitable for the simulation of large systems over long timescales. Additionally, the considerable computation time restricts DFTs ability to easily investigate a range of MHP compositions at a multi-tude of temperatures.…”

Regulating the phase stability and bandgap of quasi-2D Dion–Jacobson CsSnI3 perovskite via intercalating organic cations

“…All-inorganic lead halide perovskites (CsPbI 3 ) with great potential as next-generation solar energy absorbers have achieved their champion photovoltaic conversion efficiency (PCE) exceeding 17% 1,2 owing to their superior chemical stability, and outstanding electronic and photoelectric properties. 3–5 However, the commercial application of CsPbI 3 -based devices is severely impeded by the toxicity of the Pb element. 6 Thus, research into Pb-free and environmental friendly perovskites alternatives has emerged.…”