Details

Autor(en) / Beteiligte

• Wan, Wei
• Zhou, Ya-Yun
• Yan, Long
• Su, Binbin
• Ye, Shi

Titel

In Situ Compositing CsPbBr 3 with Exfoliated Layered-Perovskite CsCa 2 Ta 3 O 10 : Interfacial Interaction and Enhanced Stability

Ist Teil von

• ACS applied materials & interfaces, 2019-12, Vol.11 (50), p.47227-47236

Ort / Verlag

United States

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Cesium lead halide (CsPbX , X = Cl, Br, I) perovskite quantum dots (QDs) have been intriguing optoelectronic materials for applications in various devices owing to their superior electronic and optical properties. However, poor resistance to humidity and light irradiation impedes their promotion. Herein, bulk perovskite-type layered CsCa Ta O is exfoliated into two-dimensional (2D) negatively charged Ca Ta O (CTO) nanosheets as seeds to in situ synthesize and composite CsPbBr . The as-synthesized CsPbBr /CTO nanocomposites possess improved green emission with apparently prolonged decay time with reference to bare CsPbBr QDs. The decay time can retrieve to a normal state when the nanocomposites are treated with some water. It is found that the CTO acts as a defect to trap the bound exciton of the loaded CsPbBr . Protons from water can preferably replace Cs at the interface of the nanocomposites, resulting in the separation of the nanosheets and CsPbBr and retrieving the decay time. X-ray photoelectron spectroscopy results also indicate the strong interaction between CsPbBr and CTO with reference to the physical mixing sample of bare CsPbBr QDs and CTO nanosheets. The decoration of ultrathin 2D charge-bearing oxide nanosheets on the QDs benefits significant improvements in humidity resistance and photostability performance in light-emitting diode devices. This research offers a distinct strategy to modify the surface of perovskite QDs.