1. Department of Chemistry Faculty of Science Chulalongkorn University Bangkok 10330 Thailand
2. Linz Institute for Organic Solar Cells (LIOS) Institute of Physical Chemistry Johannes Kepler University Linz 4040 Austria
3. National Nanotechnology Center (NANOTEC) National Science and Technology Development Agency 111 Thailand Science Park Pathum Thani 12120 Thailand
4. Department of Materials Science and Engineering School of Molecular Science & Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Rayong 21210 Thailand