Table 1.
Photophysical and electrochemical data, and yields for intrinsic degradation of the MR-TADF dopants
| λem (nm)a,b | ΦPL (%)a,c | τPF (ns) a,d | τDF (μs) a,e | krTADF (104 s−1)f | krISC (105 s−1)g | ET1 (eV)a,h | ΔEST (eV)a,i | Eox (V vs SCE)j | Φdeg (%)k | Faradaic yield (%)l |
|
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 471 | 96 | 11 | 78 | 5.1 | 1.8 | 2.49 | 0.27 | 0.98 | 0.29 | 37 |
| 2 | 467 | 98 | 6 | 3.8 | 6.3 | 6.2 | 2.64 | 0.11 | 0.92 | 0.92 | 46 |
| 3 | 461 | 98 | 7 | 28 | 5.6 | 4.1 | 2.57 | 0.21 | 0.97 | 0.68 | 59 |
| 4 | 459 | 100 | 5 | 111 | 5.4 | 1.1 | 2.54 | 0.25 | 0.90 | 0.22 | 79 |
| 1D | 473 | 94 | 10 | 62 | 5.5 | 1.5 | 2.49 | 0.24 | 0.95 | 0.18 | 30 |
a2 wt% in PMMA films, 300 K. See Supplementary Fig. 1 for the UV−Vis absorption and photoluminescence spectra recorded in tetrahydrofuran (THF).
bEmission peak wavelength. See Supplementary Fig. 2 for the photoluminescence spectra of the PMMA films.
cPhotoluminescence quantum yield determined absolutely using an integrating sphere.
dLifetime of prompt fluorescence.
eLifetime of delayed fluorescence.
fRadiative rate constant, krTADF = ΦPL/τobs, where τobs is the average fluorescence lifetime.
gRate constant for reverse intersystem crossing, krISC = (Φtotal × kPF × kDF)/krS1.
hEnergy of the triplet state.
iThe energy difference between the singlet and the triplet excited states. Refer to Supplementary Fig. 3 for details.
jOxidation potential determined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) for Ar-saturated THF containing 1.0 mM dopant and 0.10 M tetrabutylammonium hexafluorophosphate; A glassy carbon disk and a Pt wire for the working and counter electrodes, respectively; an Ag/AgNO3 pseudo-reference electrode; scan rates = 0.1 V s −1 (CV) and 4 mV s −1 (DPV). See Supplementary Fig. 4 for the voltammograms.
kQuantum yield for photolysis.
lFaradaic yield for oxidative bulk electrolysis.