Dresden 2017 – wissenschaftliches Programm
CPP 64.6: Vortrag
Freitag, 24. März 2017, 11:00–11:15, CHE 91
Analytical Study of Solution-Processed Nickel Oxide and its Application in Organic Electronics - (1) Photoelectron Spectroscopy — •Florian Ullrich1,4, Valentina Rohnacher2,4, Jakob Bombsch3,4, Wolfram Jaegermann1,4, and Eric Mankel1,4 — 1TU Darmstadt, Materials Science Institute — 2University of Heidelberg — 3TU Braunschweig — 4InnovationLab
For the fabrication of efficient organic solar cells (OPV) suitable extraction layers are needed. A material fulfilling the requirements and leading to superior efficiencies in comparison to the standard material PEDOT:PSS is nickel oxide (NiO).
In this work we want to contribute to a more detailed understanding of the relations between annealing temperature of solution-processed NiO (sNiO), surface treatments, bulk and surface composition, structure and properties, ability to form self-assembled monolayers (SAMs) and the characteristics of sNiO-based OPV. For that purpose different analytical methods like x-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) were conducted and various OPVs were built and characterized.
In this first part we use XPS to monitor changes of band bending and surface dipoles induced by surface treatments like oxygen plasma (OP) or deposition of SAMs. These information help to explain characteristics of corresponding OPVs and provide valuable hints for the design of more efficient devices. We show how band alignment can controllably be improved by adjusting the work function via varying annealing temperature of sNiO films, OP treatment and SAM molecules.