Mobile ions determine the luminescence yield of perovskite light-emitting diodes under pulsed operation
Kumawat Naresh a, Wolfgang Tress b, Feng Gao a
a Institute of Computational Physics, Zurich University of Applied Sciences (ZHAW), 8401 Winterthur (Switzerland)
b Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden
Proceedings of Applied Light-Matter Interactions in Perovskite Semiconductors 2021 (ALMIPS2021)
Online, Spain, 2021 October 5th - 7th
Organizers: Rafael Sánchez Sánchez and Miguel Anaya
Oral, Kumawat Naresh, presentation 030
Publication date: 23rd September 2021

The external quantum efficiency of perovskite light-emitting diodes (PeLEDs) has advanced quickly during the past few years. However, under pulsed operation, an operation mode which is important for display and visible light communication, the performance of PeLEDs changes a lot and requires in-depth understanding to facilitate these applications. Here, we report the response of PeLEDs under pulsed operation in the range of 10 Hz to 20 kHz. Beyond transient effects in the low frequencies, we find that for higher frequencies (>500 Hz) the transient electroluminescence intensity depends strongly on the duty cycle. This feature is much more pronounced and of different origin than that in conventional LEDs. We rationalise our experimental observations using a mathematical model and assign these features to the effect of mobile ionic charges in the perovskite. Our work also provides important implications for the operation of PeLEDs under the steady state, where accumulation of mobile ions at the interfaces could be beneficial for high electroluminescence yields but harmful for the long-term stability.

© Fundació Scito
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info