Optical-Gain-based Sensing Using Inorganic-Ligand-Passivated Colloidal Quantum Dots
| Autor: | Xuechun Lu, Fengjia Fan, Wei-Guo Chen, Jiangfeng Du |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Steric effects
Amplified spontaneous emission Materials science Absorption of water business.industry Mechanical Engineering Bioengineering General Chemistry Trapping Condensed Matter Physics Ultrafast laser spectroscopy Molecule Optoelectronics General Materials Science Spontaneous emission business Ultrashort pulse |
| Zdroj: | Nano Letters. 21:7732-7739 |
| ISSN: | 1530-6992 1530-6984 |
| DOI: | 10.1021/acs.nanolett.1c02547 |
| Popis: | Thanks to their extremely large surface-to-volume ratio, colloidal quantum dots are potential high-performance sensing materials. However, previous sensing works using their spontaneous emission suffer from low sensitivities. The absence of an amplification process and the presence of the steric hindrance of long-chain organic ligands are two possible causations. Herein we propose that these two issues can be circumvented by using the amplified spontaneous emission of colloidal quantum dots capped by short-chain inorganic ligands. To exemplify this concept, we performed humidity sensing and observed a ∼31 times enhancement in sensitivity. Meanwhile, we found that the amplified spontaneous emission threshold power was reduced by 34% in a high humidity environment. On the basis of our transient absorption measurements, we attribute these observations to the mitigation of ultrafast subpicosecond trapping processes, which are enabled by the absorption of water molecules. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|