Novel wide-bandgap non-fullerene acceptors for efficient tandem organic solar cells. Issue 3 (19th December 2019)

• Record Type: Journal Article
• Authors: Firdaus, Yuliar; He, Qiao; Lin, Yuanbao; Nugroho, Ferry Anggoro Ardy; Le Corre, Vincent M.; Yengel, Emre; Balawi, Ahmed H.; Seitkhan, Akmaral; Laquai, Frédéric; Langhammer, Christoph; Liu, Feng; Heeney, Martin; Anthopoulos, Thomas D.
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 3(2020)
• Page Start: 1164
• Page End: 1175
• Publication Date: 2019-12-19
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta11752k
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A novel wide-bandgap non-fullerene acceptor, IDTTA, is developed. Using a PBDB-T:IDTTA system as the front-cell and a PTB7-Th:IEICO-4F blend as the back cell, we demonstrate tandem organic solar cells with 15% PCE. Abstract : The power conversion efficiency (PCE) of tandem organic photovoltaics (OPVs) is currently limited by the lack of suitable wide-bandgap materials for the front-cell. Here, two new acceptor molecules, namely IDTA and IDTTA, with optical bandgaps ( E optg) of 1.90 and 1.75 eV, respectively, are synthesized and studied for application in OPVs. When PBDB-T is used as the donor polymer, single-junction cells with PCE of 7.4%, for IDTA, and 10.8%, for IDTTA, are demonstrated. The latter value is the highest PCE reported to date for wide-bandgap ( E optg ≥ 1.7 eV) bulk-heterojunction OPV cells. The higher carrier mobility in IDTTA-based cells leads to improved charge extraction and higher fill-factor than IDTA-based devices. Moreover, IDTTA-based OPVs show significantly improved shelf-lifetime and thermal stability, both critical for any practical applications. With the aid of optical-electrical device modelling, we combined PBDB-T:IDTTA, as the front-cell, with PTB7-Th:IEICO-4F, as the back-cell, to realize tandem OPVs with open circuit voltage of 1.66 V, short circuit current of 13.6 mA cm −2 and a PCE of 15%; in excellent agreement with our theoretical predictions. The work highlights IDTTA as a promising wide-bandgap acceptor for high-performance tandem OPVs.