Tuning Phonon Energies in Lanthanide‐doped Potassium Lead Halide Nanocrystals for Enhanced Nonlinearity and Upconversion
Abstract
Optical applications of lanthanide‐doped nanoparticles require materials with low phonon energies to minimize nonradiative relaxation and promote nonlinear processes like upconversion. Heavy halide hosts offer low phonon energies but are challenging to synthesize as nanocrystals. Here, we demonstrate the size‐controlled synthesis of low‐phonon‐energy KPb2X5 (X=Cl, Br) nanoparticles and the ability to tune nanocrystal phonon energies as low as 128 cm−1. KPb2Cl5 nanoparticles are moisture resistant and can be efficiently doped with lighter lanthanides. The low phonon energies of KPb2X5 nanoparticles promote upconversion luminescence from higher lanthanide excited states and enable highly nonlinear, avalanche‐like emission from KPb2Cl5 : Nd3+ nanoparticles. The realization of nanoparticles with tunable, ultra‐low phonon energies facilitates the discovery of nanomaterials with phonon‐dependent properties, precisely engineered for applications in nanoscale imaging, sensing, luminescence thermometry and energy conversion.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 15, 2022
- Source ID
- 10.1002/ange.202212549
Entities
People
- Artiom Skripka
- Bruce E Cohen
- Chaochao Dun
- Daniel Jaque
- Emory M Chan
- Jakob C. Dahl
- Jeffrey J Urban
- Peter James Schuck
- Zhuolei Zhang
Organizations
- Columbia University
- Defense Advanced Research Projects Agency
- Huazhong University of Science and Technology
- Lawrence Berkeley National Laboratory
- Office of Basic Energy Sciences
- University of California, Berkeley
- University of Granada Faculty of Sciences