What is the effect of the recombination rates on the efficiency of TADF OLEDs?→

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What is the effect of the recombination rates on the efficiency of TADF OLEDs?

OLEDs made by thermally-activated delayed fluorescence (TADF) materials as emitters promise an IQE of 100%. Here, we want to present an analysis of the influence of non-radiative recombination rates (knrs and knrt) on the device efficiency as well as how to determine them from experiments. As we will see, the knr rate influences PLQY, and consequently ELQY, hence the negative impact on EQE.
First, to determine the non-radiative decay rates, we need to extract the rates kf, krisc, and kisc by fitting transient photoluminescence (trPL) measurements of TADF films.

Check the full discussion here: https://www.fluxim.com/determining-non-radiative-decay-rates-in-tadf-compounds

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Optimization of Charge Transport in Fluorescent Doped TADF OLEDs→

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Optimization of Charge Transport in Fluorescent Doped TADF OLEDs

We present a combined experimental/simulation analysis of a set of 4 OLEDs with 2 systematically varied guest dopants in the EML. A numerical electro-optical model is employed, demonstrating one consistent parameter set that describes both steady-state and AC characteristics of all devices. The model accounts for charge transport, trapping, polar layers, and excitonic loss processes. These are inducing an efficiency roll-off that can be correlated with the shape of the emission zone and the guest dopant concentrations. Furthermore, starting from the resulting parameter set, we show routes for optimized TADF OLDEs with a reduced roll-off.

Check the full discussion here: https://www.fluxim.com/tadf-oled-optimization-excitons

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How much bluer can you tune your blue emitting OLED? →

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How much bluer can you tune your blue emitting OLED?

In this tutorial, we are demonstrating how to use the optical module of Setfos in order to demonstrate how much the color point of a full OLED can be tuned for a given emitter spectrum. Moreover, we compare the efficiency of the color-optimized device with the one that is tuned for the highest outcoupling/radiance and analyze the consequent trade-off between color purity and efficiency.

The same analysis and optimization can be performed for other types of emitters such as quantum dots or perovskites. Despite the narrow emission spectra of these emitters, the optics of such QLEDs and PeLEDs is equal to the well-established OLEDs.

Check the full discussion here: https://www.fluxim.com/optimization-of-a-blue-oled-cavity

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Light Conversion using Perovskite Quantum Dots→

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Light Conversion using Perovskite Quantum Dots

Quantum dots are crystalline semiconductor particles with a size of a few nanometers. The nanocrystal properties are essentially determined by their size.

This blog post will present the main properties of quantum dots and their application. Moreover, it gives an example of how to characterize films with embedded quantum dots using our angular resolved spectrometer Phelos, together with our electro-optical simulation software Setfos.

Check the full discussion here: www.fluxim.com/light-conversion-perovskite-quantum-dots

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Hyperfluorescent OLED Simulation with Setfos→

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Hyperfluorescent OLED Simulation with Setfos

Fluorescence‐based organic light‐emitting diodes (OLEDs) using thermally activated delayed fluorescence (TADF) have increasingly attracted attention in research and industry. Even though the experimental realization of this concept has demonstrated promising external quantum efficiencies, the full potential of this approach has not yet been assessed. To this end, a comprehensive electro‐optical device model accounting for the full exciton dynamics, including triplet harvesting and exciton quenching is presented.

Check the full discussion here: https://www.fluxim.com/tadf-oled-simulation

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