In blue quantum dot light emitting diodes(QLEDs),electron injection is insufficient,which would degrade device efficiency and stability.Herein,we employ chlorine passivated ZnO nanoparticles as electron transport laye...In blue quantum dot light emitting diodes(QLEDs),electron injection is insufficient,which would degrade device efficiency and stability.Herein,we employ chlorine passivated ZnO nanoparticles as electron transport layer to facilitate electron injection into QDs effectively.Moreover,it suppresses exciton quenching at the QD/ZnO interface by blocking charge transfer channel.As a result,the maximum external quantum efficiency of blue QLED was increased from 2.55%to 4.60%,and the operation lifetime of blue QLED was nearly 4 times longer than that of the control device.Our work indicates that election injection plays an important role in blue QLED efficiency and stability.展开更多
We present dC/dV analysis based on the capacitance-voltage(C–V)measurement of quantum-dot lightemitting diodes(QLEDs),and find that some key device operating parameters(electrical and optical turn-on voltage,peak cap...We present dC/dV analysis based on the capacitance-voltage(C–V)measurement of quantum-dot lightemitting diodes(QLEDs),and find that some key device operating parameters(electrical and optical turn-on voltage,peak capacitance,maximum efficiency)can be directly related to the turning points and maximum/minimum of the dC/dV(versus voltage)curve.By the dC/dV study,the behaviors such as low turn-on voltage,simultaneous electrical and optical turn-on process,and carrier accumulation during the device aging can be well explained.Moreover,we perform the C–V and dC/dV measurement of aged devices,and confirm that our dC/dV analysis is correct for them.Thus,our dC/dV analysis method can be applied universally for QLED devices.It provides an in-depth understanding of carrier dynamics in QLEDs through simple C–V measurement.展开更多
基金Project supported by the National Key R&D Program of China(Grant Nos.2016YFB0401702 and 2017YFE0120400)the National Natural Science Foundation of China(Grant Nos.62005114,62005115,and 61875082)+5 种基金Key-Area Research and Development Program of Guangdong Province,China(Grant Nos.2019B010925001 and 2019B010924001)Guangdong University Key Laboratory for Advanced Quantum Dot Displays and Lighting(Grant No.2017KSYS007)Natural Science Foundation of Guangdong Province,China(Grant No.2017B030306010)Guangdong Basic and Applied Basic Research Foundation,China(Grant No.2019A1515110437)Shenzhen Peacock Team Project(Grant No.KQTD2016030111203005)High Level University Fund of Guangdong Province,China(Grant No.G02236004).
文摘In blue quantum dot light emitting diodes(QLEDs),electron injection is insufficient,which would degrade device efficiency and stability.Herein,we employ chlorine passivated ZnO nanoparticles as electron transport layer to facilitate electron injection into QDs effectively.Moreover,it suppresses exciton quenching at the QD/ZnO interface by blocking charge transfer channel.As a result,the maximum external quantum efficiency of blue QLED was increased from 2.55%to 4.60%,and the operation lifetime of blue QLED was nearly 4 times longer than that of the control device.Our work indicates that election injection plays an important role in blue QLED efficiency and stability.
基金supported by the Key-Area Research and Development Program of Guangdong Province(Grant Nos.2019B010925001 and 2019B010924001)the Shenzhen Peacock Team Project(Grant Nos.KQTD20160301 and 11203005)Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting(Grant Nos.ZDSYS201707 and 281632549)。
文摘We present dC/dV analysis based on the capacitance-voltage(C–V)measurement of quantum-dot lightemitting diodes(QLEDs),and find that some key device operating parameters(electrical and optical turn-on voltage,peak capacitance,maximum efficiency)can be directly related to the turning points and maximum/minimum of the dC/dV(versus voltage)curve.By the dC/dV study,the behaviors such as low turn-on voltage,simultaneous electrical and optical turn-on process,and carrier accumulation during the device aging can be well explained.Moreover,we perform the C–V and dC/dV measurement of aged devices,and confirm that our dC/dV analysis is correct for them.Thus,our dC/dV analysis method can be applied universally for QLED devices.It provides an in-depth understanding of carrier dynamics in QLEDs through simple C–V measurement.
