1. Department of Structure and Dynamics of Energy Materials; Helmholtz-Zentrum für Materialien und Energie; Hahn-Meitner-Platz 1 14109 Berlin Germany
2. Davidson School of Chemical Engineering; Purdue University; 480 Stadium Mall Dr. West Lafayette IN 47901 USA
3. Institute Competence Centre Photovoltaics Berlin; Helmholtz-Zentrum Berlin für Materialien und Energie; Schwarzchildstraße 3 12489 Berlin Germany