All-Inorganic Quantum Dot Light-Emitting Diodes with Suppressed Luminance Quenching Enabled by Chloride Passivated Tungsten Phosphate Hole Transport Layers
Autor: | Jianhua Zhang, Tian Jiang, Lingmei Kong, Fan Cao, Xuyong Yang, Lin Wang, Weihong Hua, Qianqian Wu, Yizhen Sui, Yongjiang Dou, Sheng Wang |
---|---|
Rok vydání: | 2021 |
Předmět: |
Materials science
chemistry.chemical_element 02 engineering and technology Tungsten 010402 general chemistry 01 natural sciences Chloride law.invention Biomaterials law medicine General Materials Science Diode Quenching business.industry General Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences chemistry Quantum dot Optoelectronics Quantum efficiency 0210 nano-technology business Luminescence Biotechnology medicine.drug Light-emitting diode |
Zdroj: | Small (Weinheim an der Bergstrasse, Germany). 17(19) |
ISSN: | 1613-6829 |
Popis: | Although excellent performance such as high efficiency and stability have been achieved in quantum dot (QD)-based light-emitting diodes (QLEDs) possessing an organic/inorganic hybrid device structure, the highly expected all-inorganic QLEDs remain at the bottleneck stage in recent years, resulting from the luminance quenching of QDs caused by inorganic hole transport layer (HTL) and unbalanced charge injection due to large energy barrier for injecting holes from HTL to QDs. Here, it is reported that the solution-processed inorganic environmentally friendly chloride (Cl)-passivated tungsten phosphate (Cl@TPA) films serve as HTL. The incorporation of Cl in TPA effectively passivates the oxygen vacancies, which not only avoids the luminescence quenching of QDs by reducing carrier concentration but also facilitates the hole injection from HTL to QDs with a favorable electronic band alignment, thus achieving the record external quantum efficiency of ≈9.27%, among all previous reports about all-inorganic QLEDs. Most importantly, the resulting all-inorganic QLEDs with Cl@TPA exhibit a substantial improvement in the operational lifetime (T50 > 105 h under an initial luminance of 100 cd m-2 ), which is almost 30-fold higher than the devices with TPA HTL. This work furnishes a promising strategy for highly efficient and stable QLEDs based on inorganic device structure. |
Databáze: | OpenAIRE |
Externí odkaz: |