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