Columnar liquid crystals as stability enhancing hole transport layers for Ruddlesden–Popper perovskite optoelectronics. Issue 7 (6th April 2022)

• Record Type: Journal Article
• Authors: Ain, Qurat ul; Siddique, Sumera; Ali, Shahzad Akhtar; Ahmed, Hasan; Khan, Mohsin; Saleem, Murtaza; Rehman, Habib ur; Ulhaq, Ata; Khan, Ammar A.
• Is Part Of: Molecular Systems Design and Engineering. Volume 7:Issue 7(2022)
• Page Start: 767
• Page End: 779
• Publication Date: 2022-04-06
• Subjects: Chemistry -- Molecular aspects -- Periodicals; Chemical engineering -- Molecular aspects -- Periodicals; Nanotechnology -- Periodicals; 620.5
• DOI: 10.1039/d1me00169h
• Languages: English
• ISSNs: 2058-9689

Abstract

Abstract : The stability of Ruddlesden–Popper perovskite (RPP) films is studied. A triphenylene discotic liquid crystal is compared with spiro-OMeTAD as an alternative hole transport layer. Results show improvement in the stability of the RPPs. Abstract : Metal halide perovskites are highly promising materials for next generation optoelectronic devices, but they suffer from moisture-driven and thermal degradation. We focus on the prototypical light-absorbing methylammonium lead(ii ) iodide (MAPbI3 ) crystal that degrades predominantly into lead iodide (PbI2 ). In this work, we perform a systematic comparison of the structural and optical properties between perovskites coated with spiro-OMeTAD and a discotic liquid crystal (DLC) 2, 3, 6, 7, 10, 11-hexakis(pentyloxy)triphenylene (HAT5). Butylammonium iodide (BAI) is used as an additive to make hybrid mixed dimensional (MD) and two-dimensional perovskites. We perform aging studies in a lab environment over a period of 45 days and two sets of conditions are tested; the first set is exposed to humidity that varies between 58 and 36%, and the second set was exposed to the environment and additionally was heated at 65 °C in the atmosphere for four hours every day. Our results demonstrate that the DLC HAT5 molecule results in improved long-term stability of hybrid MD BAI substituted Ruddlesden–Popper perovskites. Some concerns about low phase transition temperatures in working devices are also highlighted. The enhanced stability of perovskite-based optoelectronic devices with the use of HAT n HTLs provides a promising molecular engineering approach that can be applied in stable next-generation perovskite optoelectronic devices.