Synthesis and photovoltaic application of low-bandgap conjugated polymers by incorporating highly electron-deficient pyrrolo[3,4-d]pyridazine-5,7-dione units

A pyrrolopyridazinedione-based copolymer for fullerene-free organic solar cells

This study deals with the synthesis and thorough characterization of the conjugated polymer T-EHPPD-T-EHBDT, which shows promising performance in polymer/non-fullerene acceptor organic solar cells.

Novel Conjugated Polymers Prepared by Direct (Hetero) arylation: An Eco-Friendly Tool for Organic Electronics

The phthalimide (PhI) moiety has been attracting more attention as an excellent acceptor building block in donor-acceptor (D-A) conjugated polymers. In this paper; three D-A conjugated polymers with or without thiocarbonyl moieties are successfully prepared by the direct (hetero)-arylation polymerization (DHAP), which is an atom efficient and facile synthetic strategy to obtain polymer materials. Compared with the traditional carbon-carbon coupling reactions, this method possesses more advantages, including: fewer synthetic steps, avoidance of the preparation of the organometallic reagents, higher atom economy and fewer toxic byproducts, better compatibility with chemically sensitive functional groups and so on. All three of these designed PhI-based polymers exhibited favourable optoelectronic and thermal performance. The optical, thermodynamic and electrochemical properties of the synthesized polymers were systematically investigated using ultraviolet-visible (UV-vis) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and cyclic voltammetry (CV). The results of these three polymers indicated that thionation of the carbonyl was a highly effective methods to improve the properties of PhI-based polymers; and provided impetus for the development of thionated PhI derivatives for organic electronic applications.

Synthesis of a conjugated pyrrolopyridazinedione-benzodithiophene (PPD-BDT) copolymer and its application in organic and hybrid solar cells

ABSTRACT

Herein, we describe the synthesis and characterization of a conjugated donor-acceptor copolymer consisting of a pyrrolopyridazinedione (PPD) acceptor unit, and a benzodithiophene (BDT) donor unit. The polymerization was done via a Stille cross-coupling polycondensation. The resulting PPD-BDT copolymer revealed an optical bandgap of 1.8 eV and good processability from chlorobenzene solutions. In an organic solar cell in combination with PC₇₀BM, the polymer led to a power conversion efficiency of 4.5%. Moreover, the performance of the copolymer was evaluated in polymer/nanocrystal hybrid solar cells using non-toxic CuInS₂ nanocrystals as inorganic phase, which were prepared from precursors directly in the polymer matrix without using additional capping ligands. The PPD-BDT/CuInS₂ hybrid solar cells showed comparably high photovoltages and a power conversion efficiency of 2.2%.

GRAPHICAL ABSTRACT

Structure and photocatalytic activity of a low band gap donor–acceptor–donor (D–A–D) type conjugated polymer: poly(EDOT–pyridazine–EDOT)

This study presents a new low band gap D–A–D type conjugated polymer: poly(EPE). The photocatalytic activity of poly(EPE) was explored, and a possible photocatalytic degradation mechanism of dyes was proposed.

Design and synthesis of the polymers based on alkylthiophenyl side chains and variant acceptor moieties for polymer solar cells

Three new BDT-based polymers with alkylthiophenyl side chains and the relationship between the acceptor structure and the photovoltaic performance.