In a proof-of-concept study, this work demonstrates that incorporating a specifically designed block copolymer as an interfacial layer between a charge transport layer and the photoactive layer in organic solar cells can enhance the interface between these layers leading to both performance and stability improvements of the device. This is achieved by incorporating a P3HT50-b-PSSx block copolymer as an interfacial layer between the hole transporting and photoactive layers, which results in the improvement of the interfacial roughness, energy level alignment, and stability between these layers. Specifically, the incorporation of a 10 nm P3HT50-b-PSS16 and a 13 nm P3HT50-b-PSS23 interfacial layer results in a 9% and a 12% increase in device efficiency respectively compared to the reference devices. In addition to having a higher initial efficiency, the devices with the block copolymer continue to have a higher normalized efficiency than the control devices after 2200 h of storage, demonstrating that the block copolymer not only improves device efficiency, but crucially, prevents degradation by stabilizing the interface between the hole transporting layer and the photoactive layer. This study proves that appropriately designed and optimized block copolymers can simultaneously stabilize and improve the efficiency of organic solar cells.
|Journal||Advanced Materials Interfaces|
|Early online date||2 Aug 2020|
|Publication status||Published - 24 Sept 2020|
Bibliographical note© 2020 The Authors. Published by Wiley‐VCH GmbH
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Funding: National Council of Science and Technology, Mexico;
Mexico Secretary of Energy. Grant Numbers: 580474/411378, CVU 693809;
European Union Seventh Framework Programme. Grant Numbers: FP7/2011 SYNABCO, 273316, FP7/2011, 290022;
Laboratory for Process Engineering, Environment, Biotechnology and Energy – LEPABE. Grant Number: UIDB/00511/2020;
EPSRC. Grant Number: EP/M025020/1
- block copolymers
- interfacial layers
- organic solar cells
- power conversion efficiency