Open AccessResearch progress of enhancing perovskite light emitting diodes with light extraction
Author(s) -
Jiamei Chen,
Hang Su,
Luoma Wan,
Li-Lai Zhang,
Xin-Lei Suo,
Jing Qin,
Kun Zhu,
Guolong Li
Publication year - 2020
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.69.20200755
Subject(s) - optoelectronics , materials science , quantum efficiency , light emitting diode , electrode , perovskite (structure) , diode , absorption (acoustics) , luminescence , optics , composite material , physics , quantum mechanics , chemical engineering , engineering
Perovskite light emitting diodes (PeLEDs) have developed rapidly in recent years due to their advantages of tenability of band gap and high color purity. At present, the external quantum efficiency of PeLED has rised up to 20%. Like the scenario of organic light emitting diode, there exist various internal losses in PeLED with low light extraction efficiency. It arises from the absorption of substrates, waveguide transmission and surface plasmon resonance of metal electrode. To improve the luminescence performance of PeLED, a well-matched optical admittance between the thin-films inside the devices is required. In this paper, the strategies of enhancing the light extraction efficiency are adopted as the materials and structures in PeLED are concerned. The applications of alternative electrode in PeLED are discussed, such as graphene, silver nanowires, metal transparent electrode and some new-types of electrodes. In addition, the plasma effect is also introduced into the PeLED to deflect the emitting light. What is more, the nano-structure grating is inserted into device to reduce the optical losses due to the large refractive index difference between the interfaces in device. Therefore, the external quantum efficiency of PeLED rises up to 28.2%, and the current efficiency can reach 88.7 cd/A.