title: Efficient near-infrared light-emitting diodes based on liquid PbSe quantum dots.
abstract: Recently, near-infrared light-emitting diodes (NIR LEDs) based on PbSe quantum dots (QDs) have attracted considerable attention due to their facilely tunable emission wavelength, as well as high quantum yield. However, the low external quantum efficiency (EQE) of these LEDs has restricted their actual applications because of the non-radiative recombination caused by the aggregation in the solid-state QD films. Therefore, we proposed in this work to employ the liquid-type structure in NIR LEDs base on PbSe QDs, which exhibited the main advantages relying on the fact that the liquid structure could prevent the active layer from self-aggregation and improve the device stability. The emission intensity of these NIR LEDs was optimized by tuning the concentration of PbSe QDs. Besides, the radiation power of PbSe QD-based devices with different emission wavelengths was analyzed under different biases, and the maximum EQE of NIR LEDs was confirmed to be 5.3%. This result represents the highest record among the reported NIR QD-LEDs, indicating this kind of liquid-type NIR LEDs is promising for commercial applications.
authors.affiliation: State Key Laboratory on Integrated Optoelectronics and College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China. College of Material Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Xue
authors.initials: X
authors.lastname: Bai
authors.forename: Tongyu
authors.initials: T
authors.lastname: Wang
authors.forename: Long
authors.initials: L
authors.lastname: Yan
authors.forename: Tieqiang
authors.initials: T
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: William W
authors.initials: WW
authors.lastname: Yu