Solution Processed PVB/Mica Flake Coatings for the Encapsulation of Organic Solar Cells.
Iftikhar Ahmed Channa, Ali Dad Chandio, Muhammad Rizwan, Aqeel Ahmed Shah, Jahanzeb Bhatti, Abdul Karim Shah, Fayaz Hussain, Muhammad Ali Shar, Abdulaziz AlHazaa
Author Information
Iftikhar Ahmed Channa: Department of Materials and Metallurgical Engineering, Faculty of Chemical and Process Engineering, NED University of Engineering and Technology, University Road, Karachi 75270, Pakistan. ORCID
Ali Dad Chandio: Department of Materials and Metallurgical Engineering, Faculty of Chemical and Process Engineering, NED University of Engineering and Technology, University Road, Karachi 75270, Pakistan.
Muhammad Rizwan: Department of Materials and Metallurgical Engineering, Faculty of Chemical and Process Engineering, NED University of Engineering and Technology, University Road, Karachi 75270, Pakistan.
Aqeel Ahmed Shah: Department of Materials and Metallurgical Engineering, Faculty of Chemical and Process Engineering, NED University of Engineering and Technology, University Road, Karachi 75270, Pakistan.
Jahanzeb Bhatti: Department of Materials and Metallurgical Engineering, Faculty of Chemical and Process Engineering, NED University of Engineering and Technology, University Road, Karachi 75270, Pakistan. ORCID
Abdul Karim Shah: Department of Chemical Engineering, Dawood University of Engineering and Technology, Karachi 74800, Pakistan.
Fayaz Hussain: Modeling Evolutionary Algorithms Simulation and Artificial Intelligence, Faculty of Electrical & Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam. ORCID
Muhammad Ali Shar: King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451, Saudi Arabia. ORCID
Abdulaziz AlHazaa: King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451, Saudi Arabia. ORCID
Organic photovoltaics (OPVs) die due to their interactions with environmental gases, i.e., moisture and oxygen, the latter being the most dangerous, especially under illumination, due to the fact that most of the active layers used in OPVs are extremely sensitive to oxygen. In this work we demonstrate solution-based effective barrier coatings based on composite of poly(vinyl butyral) (PVB) and mica flakes for the protection of poly (3-hexylthiophene) (P3HT)-based organic solar cells (OSCs) against photobleaching under illumination conditions. In the first step we developed a protective layer with cost effective and environmentally friendly methods and optimized its properties in terms of transparency, barrier improvement factor, and bendability. The developed protective layer maintained a high transparency in the visible region and improved oxygen and moisture barrier quality by the factor of ~7. The resultant protective layers showed ultra-flexibility, as no significant degradation in protective characteristics were observed after 10 K bending cycles. In the second step, a PVB/mica composite layer was applied on top of the P3HT film and subjected to photo-degradation. The P3HT films coated with PVB/mica composite showed improved stability under constant light irradiation and exhibited a loss of <20% of the initial optical density over the period of 150 h. Finally, optimized barrier layers were used as encapsulation for organic solar cell (OSC) devices. The lifetime results confirmed that the stability of the OSCs was extended from few hours to over 240 h in a sun test (65 °C, ambient RH%) which corresponds to an enhanced lifetime by a factor of 9 compared to devices encapsulated with pristine PVB.
