Fig. 2
Cyclic voltammetry (CV) and optical measurements of device materials. a–d CV traces recorded on thin films of the different host and guest constituents, with the corresponding chemical structure displayed in the right inset. e CV for the THABF4 electrolyte (solid line) and a TMPE-OH:LiCF3SO3 electrolyte (dashed line). f The electron-energy levels of the host and guest materials, as extracted from the CV data. The (dotted) LUMO level of PVK could not be measured with CV, and was instead estimated from the absorption data. g The triplet energies of the host and guest compounds. h The absorption spectrum of the guest compound (solid black line) and the PL spectra of the three host materials
