Cubic CsPbI₃ Nanoarchitectonics with High and Stable Photoluminescence toward White Light-Emitting Diodes

Abstract

The poor stability of cesium lead iodide (CsPbI3) perovskite nanocrystals (NCs) under light and humidity conditions limits their practical application. The dynamic binding of ligands is easy to desorb during the purification process, which results in a deterioration of their optical performance and stability. In this paper, sodium dodecyl benzene sulfonate (SDBS) was used to modify the surface of CsPbI3 NCs. By utilizing the strong combined effect of benzenesulfonic acid and Pb ions, the poor stability caused by the loss of weakly interacting amine ligands was effectively improved; meanwhile, the I ion vacancies can be filled to inhibit the occurrence of nonradiative recombination, so that the optical performance of the CsPbI3 NCs is improved. The radiative and nonradiative recombination process during photoluminescence is deeply discussed. After modification, the photoluminescence quantum yields of CsPbI3 NCs reached 90.7%, the superior photoluminescence intensity still retained 83% of the initial intensity after being stored for 60 days under environmental conditions, and the stability in water was remarkably improved. Additional SDBS was used after purification, suggesting that the presence of SDBS can effectively improve photostability. This method offers a new idea for preparing high-performance perovskite-based devices.

Slowing Down the Hot Carrier Relaxation Dynamics of CsPbX3 Nanocrystals by the Surface Passivation Strategy

“…Observation confirms the attachment of the Br – ions with the −NH 3 + group of HDA molecules. The presence of strong N1s spectra further verifies the effective passivation with HDA on the surface of the CsPbBr 3 NCs. ,, The attachment of HDA molecule to the NC surface is further verified with the help of FTIR analysis (Figure S6). The FTIR peaks at 2923, 2854, and 1466 cm –1 are attributed to the C–C and C–H stretching modes of the CH 2 group and −COO stretching, respectively.…”

Defects in lead halide perovskite light-emitting diodes under electric field: from behavior to passivation strategies

“…10d, the anchoring effect of sulfonate groups on the surface of CsPbBr 3 NCs effectively minimizes exciton trapping and confers enhanced stability against degradation throughout purification, storage, and irradiation processes. 176 Sodium dodecyl benzene sulfonate (SDSA) 177 exhibits a notable affinity for CsPbI 3 NCs due to –SO 3− in the ligand strongly binding with uncoordinated Pb 2+ and filling the V I . The inclusion of SDSA sustained a PL intensity of 83% after 60 days of environmental exposure.…”

CsPbX3 (X = Cl, Br, and I) Nanocrystals in Substrates toward Stable Photoluminescence: Nanoarchitectonics, Properties, and Applications

“…The display device has become one of the most important information output instruments in modern society and has been widely utilized in a variety of devices involving cell phones, computers, televisions, etc. , Among these, light-emitting diodes (LEDs) constructed using luminescent semiconductor nanocrystals (NCs) have emerged as one of the leading technologies in the flat-panel displays market. , Unlike classic colloidal II–VI (e.g., CdTe and CdSe), III–V (e.g., InP), and ternary I–III–VI (e.g., CuInS 2 ) NCs, luminescent perovskite materials often possess relatively low nonradiative recombination rates and high color purity, which make them competitive candidates in the fields of LEDs and lasers. − Because of the rich morphologies (in the form of nanoplatelets (NPLs), nanosheets (NSs), nanowires (NWs), quantum dots (QDs), etc.) and abundant structures (ranging from zero dimensional (0D) to three-dimensional (3D)) as well as the outstanding photoluminescence (PL) properties of the perovskite nanomaterials, these materials have been widely studied for a variety of applications.…”