1. Departement of Industrial Chemistry, Addis Ababa Sciences and Technology University, P.O. Box 16417, Addis Ababa 1165, Ethiopia
2. Sustainable Energy Center of Excellence, Addis Ababa Sciences and Technology University, P.O.
Box 16417, Addis Ababa 1165, Ethiopia
3. Linz Institute for Organic Solar Cells (LIOS), Institute of Physical Chemistry, Johannes Kepler University, Altenberger Str.69, Linz 4040, Austria
4. Division of Soft Matter Physics and LIT Soft Materials Lab, Johannes Kepler University, Linz, Altenberger Street 69, Linz 4040, Austria
5. Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa 1165, Ethiopia