Figure 6.
Understanding the effect of UVO and O2 plasma treatments. (a) Electronic structure at the np-SnO2 surface with the Fermi level (EF) from UPS measurements, valence band from UPS and XPS and estimated conduction band from the optical band gap. (b) Stabilized light-VOC measurements for 120 + UVO and 120 + O2 devices, showing reduced VOC for the plasma treatment. Apparent nid from linear fits are shown, and in the O2 plasma case, behavior indicates increased nonradiative recombination at the ETL interface.64,67