CHNHPbBr perovskite nanocrystals (NCs) suffer from poor stability because of their high sensitivity to environmental moisture and water. To solve this problem, previous works mainly focus on embedding perovskite NCs into water-resistant matrix to form large composites (size of microns or larger). As an alternative solution without serious changing of NC size, enhancing the stability of perovskite NCs themselves by ligand engineering is rarely reported. In this work, we used hyperbranched polyamidoamine (PAMAM) dendrimers with two different generations (G0 and G4) to synthesize CHNHPbBr perovskite NCs with high photoluminescence (PL) quantum yields (QY) above 70% and a new record stability. A novel dendrimers generation-dependent stability of perovskite NCs was observed. The water-resistance time is 18 h (27 h) for perovskite NCs capped by G0 (G4) generation of PAMAM, which is 7 times (11 times) longer than that of traditional oleic acid-capped NCs. Similar PAMAM generation-related stability is also observed in moisture-resistance tests. The stability time against moisture is 500 h (800 h) for G0 (G4) generation of PAMAM-capped perovskite NCs, which is a new record stability time against moisture for CHNHPbBr perovskite NCs. In addition, our results also indicate that PAMAM ligands outside perovskite NCs can dramatically slow down the speed of halide exchange. Even for the mixture of perovskite NCs with two different halide composition, the original luminescence properties of PAMAM-capped perovskite NCs can retain after mixing. In view of slow halide exchange speed, excellent water and moisture stability, PAMAM dendrimers-capped perovskite NCs and their mixture are available as color conversion single layer in fabrication of light-emitting diodes (LED).

Download full-text PDF

Source
http://dx.doi.org/10.1088/1361-6528/aab93bDOI Listing

Publication Analysis

Top Keywords

perovskite ncs
44
chnhpbbr perovskite
16
perovskite
13
ncs
13
halide exchange
12
record stability
12
stability
9
perovskite nanocrystals
8
moisture water
8
stability perovskite
8

Similar Publications

Oxygen Activation Biocatalytic Precipitation Strategy Based on a Bimetallic Single-Atom Catalyst for Photoelectrochemical Biosensing.

Anal Chem

January 2025

Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, MOE; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.

Article Synopsis
  • The traditional biocatalytic precipitation (BCP) method has limitations due to HO's tendency to self-decompose, affecting its effectiveness in quantitative analysis.
  • Researchers discovered that a bimetallic single-atom catalyst (Co/Zn-N-C SAC) can activate dissolved oxygen to create reactive oxygen species, leading to improved detection methods.
  • The development of a new oxygen-activated photoelectrochemical (PEC) biosensor for chloramphenicol (CAP) detection demonstrates enhanced stability and accuracy by using Co/Zn-N-C SAC and cesium platinum bromide nanocrystals (CsPtBr NCs) without needing external reactants.
View Article and Find Full Text PDF

Crystallization of CsPbBr Nanocrystals within a Melt-Quenched Glassy Coordination Polymer.

ACS Nano

January 2025

Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, LIFM, GBRCE for Functional Molecular Engineering, School of Chemistry, IGCME, Sun Yat-Sen University, Guangzhou 510275, China.

Lead halide perovskite nanocrystal materials such as CsPbX (X = Cl, Br, and I) have triggered an intense research upsurge due to their excellent scintillation performance. Herein, an crystallization strategy is developed to grow CsPbBr nanocrystals (NCs) within a low-melting-point (280 °C) coordination polymer (CP) glass. The viscosity of coordination glass is reduced through a low-temperature (e.

View Article and Find Full Text PDF

So far, the striking sign reversal in the near-ambient slope of the gap temperature dependence of colloidal CsPbCl perovskite nanocrystals (NCs) compared to its Br counterpart remains unresolved. Pure bromide NCs exhibit a linear gap increase with increasing temperature, to which thermal expansion and electron-phonon interaction equally contribute. In contrast, the temperature slope for the chlorine compound gap is clearly negative.

View Article and Find Full Text PDF

Phonon Involved Photoluminescence of Mn Ions Doped CsPbCl Micro-Size Perovskite Assembled Crystals.

Adv Sci (Weinh)

January 2025

State Key Laboratory of Solidification Processing, Center for Nano Energy Materials, School of Materials Science and Engineering, Northwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene (NPU), Xi'an, 710072, P. R. China.

Mn ions doped CsPbCl perovskite nanocrystals (NCs) exhibit superiority of spin-associated optical and electrical properties. However, precisely controlling the doping concentration, doping location, and the mono-distribution of Mn ions in the large-micro-size CsPbCl perovskite host is a formidable challenge. Here, the micro size CsPbCl perovskite crystals (MCs) are reported with uniform Mn ions doping by self-assembly of Mn ions doped CsPbCl perovskite NCs.

View Article and Find Full Text PDF

This study investigates the photophysical behaviour of Mn/Fe and Mn/Sn co-doped CsPbCl3 perovskite nanocrystals (NCs) to explore carrier dynamics and dopant interactions. Using gated photoluminescence (PL) and temperature-dependent measurements, we elucidate the impact of dopant chemistry on exciton behaviour, focusing on vibrationally assisted delayed fluorescence (VADF) and energy transfer mechanisms. The efficiency of VADF is influenced by factors such as the bandgap, temperature, quantum confinement, and host composition.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!