Synthesis and characterization of porphyrin‐based D‐π‐A conjugated polymers for polymer solar cells

Abstract

Two novel porphyrin‐based D‐A conjugated copolymers, PFTTQP and PBDTTTQP, consisting of accepting quinoxalino[2,3‐b′]porphyrin unit and donating fluorene or benzo[1,2‐b:4,5‐b′]dithiophene unit, were synthesized, respectively via a Pd‐catalyzed Stille‐coupling method. The quinoxalino[2,3‐b′]porphyrin, an edge‐fused porphyrin monomer, was used as a building block of D‐A copolymers, rather than the simple porphyrin unit in conventional porphyrin‐based photovoltaic polymers reported in literature, to enhance the coplanarity and to extend the π‐conjugated system of polymer main chains, and consequently to facilitate the intramolecular charge transfer (ICT). The thermal stability, optical, and electrochemical properties as well as the photovoltaic characteristics of the two polymers were systematically investigated. Both the polymers showed high hole mobility, reaching 4.3 × 10−4 cm2 V−1 s−1 for PFTTQP and 2.0 × 10−4 cm2 V−1 s−1 for PBDTTTQP. Polymer solar cells (PSCs) made from PFTTQP and PBDTTTQP demonstrated power conversion efficiencies (PCEs) of 2.39% and 1.53%, both of which are among the highest PCE values in the PSCs based on porphyrin‐based conjugated polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Photoresponsive polyamides containing pentamethylated norbornadiene moieties: Synthesis and photochemical properties under sunlight irradiation

“…Photoresponsive and electron conducting polymer materials are crucial components in applications such as solar cells, photovoltaics, organic electronics, and holographic data storage . Among the broad range of photoactive materials, the isomerization between norbornadiene (NBD) and quadricyclane (QC) is a promising system for the development of materials suitable for the storage and conversion of solar energy .…”

Porphyrin polymers and organic frameworks

“…Further work on the quinoxaline porphyrin D-A polymer system involved substituting the carbazole for a fluorene or benzodithiophene moiety, but these had limited effect on the photovoltaic performance with solar conversion efficiencies of 2.39% for the fluorene-containing polymer and 1.53% for the benzodithiophene-containing porphyrin polymer (Figs 39(j) and (k)). 113 Although these systems show good visible-light photovoltaic response, performance appears to be limited by low free charge carrier transport within the photoactive layer. Charge mobility and an overall increase in efficiency was recently obtained with a thiophen-2-ylbenzo-2,1,3-thiadiazole-based system which appended a diethynyl-containing porphyrin along the conjugated polymer backbone (Fig.…”

“…Hole mobilities may be limited by the close interaction between the porphyrin and the polymer chain forcing nonlinearity in the conjugated backbone. Further work on the quinoxaline porphyrin D–A polymer system involved substituting the carbazole for a fluorene or benzodithiophene moiety, but these had limited effect on the photovoltaic performance with solar conversion efficiencies of 2.39% for the fluorene‐containing polymer and 1.53% for the benzodithiophene‐containing porphyrin polymer (Figs (j) and (k)) . Although these systems show good visible‐light photovoltaic response, performance appears to be limited by low free charge carrier transport within the photoactive layer.…”

Porphyrins and BODIPY as Building Blocks for Efficient Donor Materials in Bulk Heterojunction Solar Cells

“…However, their use as pendent groups has actually proven their potential. For example, H. Wang et al have reported the synthesis of several conjugated polymers alternating electron‐rich units and poor “β‐fused” quinoxalino[2,3‐ b' ]porphyrins . Among these compounds, C‐TT‐QP and C‐TT‐QP‐Zn are composed of carbazole units and fused porphyrins which are separated by terthiophene bridges.…”