Impact of Chalcogenophenes on Donor-Acceptor Copolymers for Bulk Heterojunction Solar Cells

Abstract

Three new selenophene-based conjugated copolymers having different ratios of the monomeric units were designed, synthesized and thoroughly characterized. The introduction of an electron-poor and surfaced building moiety like selenathiazole was highly efficient in tuning the bandgap and polymer properties. The chalcogenophene-based medium-bandgap polymers demonstrated low-lying HOMO energy levels (~5.87 eV), which is benign for use in multi-junction polymer solar cell applications. The representative polymers with heavy atoms revealed the change in electronegativity and atomic size that highly affected the molecular property, its topological features, and photovoltaic properties in polymer solar cells. The selenium-substituted (0.5:0.5) polymer donors showed power conversion efficiencies above 3% when combined with [6,6]-phenyl-C71-butyric acid methyl ester (PC 7 0 BM) acceptors in a quintessential bulkheterojunction solar cell.

Cathode Interlayer Based on Naphthalene Diimide: A Modification Strategy for Zinc-Oxide-Free Inverted Organic Solar Cells

“…Organic solar cells (OSCs) have drawn a lot of interest as a low-cost renewable energy source with large-scale capabilities on various substrates. − As a result, power conversion efficiencies (PCEs) have significantly improved, which have exceeded 20%. − The advancements were acquired by the discovery of an effective active layer, the modification of photoactive layer morphology, and the enhancement of interface properties …”

Side‐chain engineering of regioregular copolymers for high‐performance polymer solar cells processed with nonhalogenated solvents

“…In the past two decades, tremendous efforts have been devoted to the development of novel materials, morphology control, and device optimization to attain improved power conversion efficiency (PCE) over 19% in single-junction PSCs. [1][2][3][4][5][6][7][8][9] Despite rapid development, most of the highperformance conjugated polymer for BHJ PSCs are processed with halogenated solvents such as chloroform (CF), chlorobenzene (CB), and 1,2-dichlorobenzene (DCB), which can cause difficulties due to their toxicity, cost, and environmental concerns. [10][11][12][13] Recently, conjugated copolymers based on 5-fluorobenzo[c] [1,2,5]thiadiazole (fBT) have attracted much attention because they have many advantages such as broad absorption ability, proper energy levels, high charge carrier, and excellent charge carrier mobility.…”

“…Bulk heterojunction polymer solar cells (BHJ PSCs) have received great attention due to their merits such as low‐cost, lightweight, flexibility, and roll‐to‐roll process. In the past two decades, tremendous efforts have been devoted to the development of novel materials, morphology control, and device optimization to attain improved power conversion efficiency (PCE) over 19% in single‐junction PSCs 1–9 . Despite rapid development, most of the high‐performance conjugated polymer for BHJ PSCs are processed with halogenated solvents such as chloroform (CF), chlorobenzene (CB), and 1,2‐dichlorobenzene (DCB), which can cause difficulties due to their toxicity, cost, and environmental concerns 10–13 …”

Strong Bathochromic Shift of Conjugated Polymer Nanowires Assembled with a Liquid Crystalline Alkyl Benzoic Acid via a Film Dispersion Process

“…Conjugated polymers are a popular material for optoelectronic, 1 biomedical, 2 and energy applications 3 because of their semiconducting properties and versatility in modulating their properties by adjusting their chemical structures. Through intra- and intermolecular charge transfer in assemblies of conjugated polymers, charge carriers can efficiently transport to enhance the efficiency of field-effect transistors (FETs), 4 − 6 light-emitting diodes (LEDs), 7 − 9 and photovoltaic cells. 10 − 12 In addition, they can efficiently harvest energy from a wide range of light, from ultraviolet (UV) to near-infrared (NIR) regions, by conveniently adjusting their band gaps, and either emit the energy as light or heat or transport it to other materials.…”

“…Conjugated polymers are a popular material for optoelectronic, biomedical, and energy applications because of their semiconducting properties and versatility in modulating their properties by adjusting their chemical structures. Through intra- and intermolecular charge transfer in assemblies of conjugated polymers, charge carriers can efficiently transport to enhance the efficiency of field-effect transistors (FETs), − light-emitting diodes (LEDs), − and photovoltaic cells. − In addition, they can efficiently harvest energy from a wide range of light, from ultraviolet (UV) to near-infrared (NIR) regions, by conveniently adjusting their band gaps, and either emit the energy as light or heat or transport it to other materials. Accordingly, they have been considered an ideal material for photoluminescence imaging − and sensing, − photoacoustic imaging − and photothermal therapy upon heat generation, − and photocatalysis reactions by efficient light harvesting. ,, The preparation of nanowires has been important for enhancing the performance in these applications.…”