An Interlocking Fibrillar Polymer Layer for Mechanical Stability of Perovskite Solar Cells. Issue 23 (9th October 2020)

• Record Type: Journal Article
• Authors: Jeong, Seonju; Lee, Inhwa; Kim, Taek‐Soo; Lee, Jung‐Yong
• Is Part Of: Advanced materials interfaces. Volume 7:Issue 23(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-09
• Subjects: defect passivation -- dopant free hole transport layers -- mechanical stability -- perovskite solar cells -- polymer fibrils; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202001425
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Atmospheric and mechanical stability of perovskite solar cells (PSCs) must be guaranteed for successful commercialization. A fibrillar polymer, poly[ N ‐9′‐heptadecanyl‐2, 7‐carbazole‐alt‐5, 5‐(4′, 7′‐di‐2‐thienyl‐2′, 1′, 3′‐benzothiadiazole)] (PCDTBT), is reported as an efficient hole transfer layer (HTL) which significantly improves air and mechanical stability of perovskite solar cells (PSCs). PCDTBT fibrils formed at the grain boundaries of perovskite layer induce the highest fracture energies in the PSCs, which provide extrinsic reinforcement and shielding for enhanced mechanical and chemical stability. Debonding energy increases by 30% for the PSCs with PCDTBT fibrils, which fractures at 2.66 J m −2, compared to the devices without PCDTBT fibrils at 2.09 J m −2 ; more importantly, the threshold debonding driving force of the PCDTBT fibril‐based devices is greatly improved by twofold under ambient conditions. Abstract : Incorporation of a poly[ N ‐9′‐heptadecanyl‐2, 7‐carbazole‐alt‐5, 5‐(4′, 7′‐di‐2‐thienyl‐2′, 1′, 3′‐benzothiadiazole)] (PCDTBT) fibrils as an efficient hole transfer layer (HTL) is demonstrated as an effective approach to significantly enhance air and mechanical stability of perovskite solar cells (PSCs) as an alternative to widely used doped HTLs, resulting from the interlocking effect of PCDTBT fibrils formed at the interface between perovskite and PDCTBT layers.