Synthesis and Photovoltaic Properties of New Multifused Anthradithiophene‐Based Narrow‐Bandgap D–A Copolymers

Abstract

Three structurally novel donor–acceptor copolymers are synthesized and fully characterized using an anthradithiophene (ADT) derivative as the donor block. All of them exhibit broad absorption ranges and moderate hole and electron mobilities. The multifused ADT donor block makes them exhibit lower highest occupied molecular orbital (HOMO) energy levels than many reported benzodithiophene‐based polymers. Copolymer blends with [6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) as active layers are used to fabricate polymer solar cells (PSCs) and a variety of post‐treatment methods are employed to optimize the device performance. The conventional and inverted configuration devices are prepared to evaluate the photovoltaic properties. A maximum power conversion efficiency of 1.66% is achieved for the inverted‐configuration device. The improved efficiency is caused by the close energy alignment between the work function of MoO3 and the HOMO energy levels of the copolymers, facilitating better charge transport and increased short‐circuit current density (Jsc) with the inverted devices.

HOMO energy level regulation of novel conjugated copolymers for polymer solar cells

“…Such high T d values indicate that these molecules possess relative stability, and may be suitable for solar cell applications. The film absorption spectrum of each of these three copolymers features two absorption bands: one at 300-500 nm, which we assign to the localized p-p* transitions, 12 and the other, a broader band in the long wavelength region, from 500 to 800 nm, which can be ascribed to the intramolecular charge transfer (ICT) between the acceptor units and the donor units. 2(a) and (b) show the absorption spectra of the synthesized polymers P1, P2, and P3 in chloroform solution and in the solid View Article Online state, respectively.…”

“…The absorption spectra of the three polymers in the solid state are similar to their corresponding solution spectra. The film absorption spectrum of each of these three copolymers features two absorption bands: one at 300-500 nm, which we assign to the localized p-p* transitions, 12 and the other, a broader band in the long wavelength region, from 500 to 800 nm, which can be ascribed to the intramolecular charge transfer (ICT) between the acceptor units and the donor units. Therefore, the random copolymers with extended light absorption could have a strong potential for achieving panchromatic PSCs.…”

Benzo[1,2-b:4,5-b′]dithiophene and Thieno[3,4-c]pyrrole-4,6-dione Based Donor-π-Acceptor Conjugated Polymers for High Performance Solar Cells by Rational Structure Modulation

“…Compounds 3 and 7 were synthesized according to the known procedures. − The polymers were prepared by the Stille coupling reaction, and the precipitations were filtered into a Soxhlet extractor. Methanol and hexane were used as solvents to remove the residual catalyst and the oligomers, successively.…”

Two-Dimensional, Acene-Containing Conjugated Polymers That Show Ratiometric Fluorescent Response to Singlet Oxygen

“…Acenes are another important class of organic semiconductors in a variety of optoelectronics applications: pentacene, rubrene, and a variety of diethynylacenes and heteroacenes are benchmark materials in thin film and single crystal transistors. , These classes of molecules have tunable optical and electrochemical properties in solution through structural modifications of both the acene core and substituents. − Several groups have reported CPs that integrate linear acenes of four or more fused rings into their π-conjugated structures for use in transistors and photovoltaics, − including pentacene and anthradithiophene-containing poly­(arylene–ethynylene)­s from the group of Bao. − …”