Isoindigo-Containing Molecular Semiconductors: Effect of Backbone Extension on Molecular Organization and Organic Solar Cell Performance
نویسندگان
چکیده
We have synthesized three new isoindigo-based small molecules by extending the conjugated length through the incorporation of octyl-thiophene units between the isoindigo core and benzothiophene terminal units. Both UV-vis and Grazing incidence X-ray diffraction experiments show that such extension of the π-conjugated backbone can induce H-aggregation, and enhance crystallinity and molecular ordering of these isoindigo-based small molecules in the solid state. Compared to two other isoindigo-based derivatives in the series, the derivative with two octyl-thiophene units, BT-T2-ID, is the most crystalline and ordered, and its molecular packing motif appears to be substantially different. Devices utilizing these new extended isoindigo-based small molecules as the electron donor exhibit higher performance than those utilizing nonextended BT-ID as the electron donor. Particularly, devices containing BT-T2-ID in an as-cast blend with PC61BM show power conversion efficiencies up to 3.4%, which is comparable to the best devices containing isoindigo-based molecular semiconductors and is a record among devices containing isoindigo-based small molecules that were processed in the absence of any additives.
منابع مشابه
Enhance performance of organic solar cells based on an isoindigo-based copolymer by balancing absorption and miscibility of electron acceptor
متن کامل
A thieno[3,2-b][1]benzothiophene isoindigo building block for additive- and annealing-free high-performance polymer solar cells.
A novel photoactive polymer with two different molecular weights is reported, based on a new building block: thieno[3,2-b][1]benzothiophene isoindigo. Due to the improved crystallinity, optimal blend morphology, and higher charge mobility, solar-cell devices of the high-molecular-weight polymer exhibit a superior performance, affording efficiencies of 9.1% without the need for additives, anneal...
متن کاملAcid azo dyes for efficient molecular photovoltaic: study of dye-sensitized solar cells performance
In this paper we sensitized three free-metal azo days Dye 1, Dye 2 and Dye 3 based on 1,8-naphthalimide with n-propyl as the electron donor group. We used sulfonic acid and hydroxyl substituents as the electron acceptor anchoring group in synthesized dyes. The proposed dyes were sensitized from acenaphthene as the starting material by standard reactions and characterized by different techniques...
متن کاملHigh open circuit voltage organic solar cells based upon fullerene free bulk heterojunction active layers
We have recently reported on a small organic molecule containing a bithiophene core with end-capping phthalimide units (PthTh2Pth) that exhibited a H-aggregation tendency in the solid state and high electron mobility in organic field effect transistors. In this contribution, we have studied both the physical and electrical properties of poly(3-hexylthiophene) (P3HT) and PthTh2Pth thin films by ...
متن کاملInvestigation of Organic Compounds as Photosensitizer for Dye Sensitized Solar Cells
Two organic compounds (SC-23=(E)-2-Cyano-3-(2,3-dimethoxyphenyl) acrylic acid and SC-25=(E)-2-Cyano-3-(2,5-dimethoxyphenyl) acrylic acid) involving methoxy groups as the electron donor and cyanoacrylic acid group as the electron acceptor have been investigated for dye sensitized solar cells. They shows a short-circuit current density (Jsc) of 2.08 and 1.81 mA cm-2, an open circuit voltage (Voc)...
متن کامل