Fig. 1: Oxygen doping chemistry in OSCs and devices.
From: Unraveling the crucial role of trace oxygen in organic semiconductors
a Intensity of the TOF-SIMS data for the C and O elements of the fresh DNTT single crystal. Inset is the 3D reconstruction of the depth profile. b Valence photoemission spectrum and secondary electron spectrum extracted from the UPS measurement of the fresh DNTT film. Ionization energy (IE), vacuum level (Evac), and injection barrier (Einject) are exacted from the UPS result, and the energy gap (Eg) is obtained from the UV-vis absorption spectrum. The energy position of the HOMO, the LUMO, and the EF are thus determined. c The EPR signals of organic radical cations (ORCs) and DMPO-•OOH (the adduct of DMPO with superoxide anions (O2−)) in fresh DNTT film, suggesting the innate oxygen doping in OSCs. d Different OSCs were used for investigation in this work.
