Two compatible nonfullerene acceptors with similar structures as alloy for efficient ternary polymer solar cells. (August 2017)

• Record Type: Journal Article
• Authors: Su, Wenyan; Fan, Qunping; Guo, Xia; Meng, Xiangyi; Bi, Zhaozhao; Ma, Wei; Zhang, Maojie; Li, Yongfang
• Is Part Of: Nano energy. Volume 38(2017:Aug.)
• Page Start: 510
• Page End: 517
• Publication Date: 2017-08
• Subjects: Ternary polymer solar cells -- Nonfullerene acceptor -- Wide-bandgap polymer -- Power conversion efficiency; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2017.05.060
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: In this work, we fabricated high efficient ternary PSCs based on two compatible non-fullerene acceptors (IDIC and ITIC) with similar chemical structures and one new D-A-type polymer (PSTZ) donor. By inserting ITIC into the binary PSTZ:IDIC system, the active layer show smooth and gradient energy levels, improved crystallinity and optimized morphologies, which results in efficient exciton separation, charge transport and collection. As a result, the optimal ternary PSCs based on PSTZ:ITIC:IDIC (1:0.1:0.9) exhibited a higher PCE of 11.1% with a V oc of 0.953 V, J sc of 17.4 mA cm −2 and FF of 66.9% in comparison with those of binary PSC systems based on PSTZ:IDIC (PCE of 8.06%) or PSTZ:ITIC (PCE of 8.13%). These results indicate that combining two compatible nonfullerene acceptors with similar structures to fabricate ternary PSCs should be a promising strategy to enhance the photovoltaic performance of the PSCs. Graphical abstract: A new wide bandgap copolymer PSTZ was synthesized and applied for photovoltaic devices. The ternary non-fullerene PSCs based on PSTZ as donor and the alloy of two compatible nonfullerene acceptors ITIC and IDIC as acceptor exhibited superior photovoltaic performance with a PCE of 11.1%, under the illumination of AM 1.5 G, 100 mW cm −2 . Highlights: A novel wide bandgap conjugated polymer (PSTZ) was synthesized. Two compatible non-fullerene acceptors (IDIC and ITIC) were combined as acceptor alloy. The PSCs based on PSTZ: ITIC: IDIC (1:0.1:0.9) exhibited a higher PCE of 11.1%.