Benzo[1,2‐b:4,5‐b′]dithiophene Building Block for the Synthesis of Semiconducting Polymers

Abstract

This review covers the synthesis and polymerization of benzo[1,2-b: 4,5-b']dithiophene (BDT) to generate semiconducting polymers used in organic field-effect transistors (OFET) and organic solar cells applications.

Structure and Morphology Control in Thin Films of Conjugated Polymers for an Improved Charge Transport

“…Firstly, extending the conjugation system and strengthening intra-chain and inter-chain interaction is a direct way to improve electronic properties. Based on the classic conjugated polymers such as P3ATs (P1), a straight strategy is inserting more conjugated moieties [3,82] such as carbon double bond (-HC=CH-, P2) [83][84][85], unsubstituted multiple or fused aromatic rings (i.e., thiophenes and thieno[3,2-b]thiophene, etc., P3-P7) [13,14,16,37,82,[86][87][88][89][90][91], other heterocyclic rings containing nitrogen(and sulfur) (P8 and P9) or selenium atoms (P10) [13,15,81,[92][93][94][95][96][97] and their combination (P11) [98]. Thus, the intra-chain conjugation is extended and strengthened by coupling with the more conjugated moieties, and the conjugation length is elongated due to the improved planarity.…”

“…Compared with inorganic semiconductors and organic π-conjugated small molecules, the family of conjugated polymers has great advantages in its low weight, easy solution-processing and suitability to industrial manufacturing of large-area devices such as roll-to-roll routes [8][9][10]. Thus, many groups of conjugated polymers have been synthesized [3,[11][12][13][14][15][16] and a extremely high carrier mobility of 12.04 cm in FETs without doping [17] and power conversion efficiency of 8.67% in single junction OPVs [18] have been realized among them, which shows a brilliant prospects of them as the next-generation electronic materials. Therefore, understanding the correlations between the intrinsic properties of conjugated polymers, the features of thin film and the performance of corresponding electronic devices become crucial to guide the synthesis of more excellent materials and achievement of better electronic properties.…”

Donor–acceptor semiconducting polymers for organic solar cells

“…Several reviews on band-gap engineering and D-A polymers for organic solar cells have been previously published. 35,[39][40][41][42][43][44][45][46][47][48] The following donor building blocks will be described in this review: 9,9-dialkyl-2,7-fluorene (FL), 2,7-carbazole (CZ), cyclopenta [2,1- (Fig. 4).…”

“…However, the HOMO of the DTP 0 ]dithiophene (BDT) is the most used donor building block for the synthesis of semiconducting polymers used in OFETs and BHJ solar cells. 45,[114][115][116] The BDT building block offers two advantages: the fused BDT allows the incorporation of substituents on the central benzene core while maintaining the planarity of the two thiophene units, and the symmetric nature of the BDT monomer eliminates the need of controlling regioregularity during the polymerization. 114 Moreover, due to the large planar conjugated structure of the BDT unit, the polymer can easily forms pÀp stacks, which renders high charge carrier mobility.…”

meso-Substituted Porphyrin with Benzo[1,2-b:4,5-b’]dithiophene Moieties

“…Among them, benzo[1,2-b:4,5-b']dithiophene (BDT) displays remarkable properties such as high-field effect mobility and -conductivity, easy tuneable low-band gap and molecular energy level control. [2][3][4][5][6][7][8] In this context, we report on the synthesis and characterisation of two tetrakis BDT-mesosubstituted porphyrins, T-H (free-base) and T-Zn (zinc; see Figure 1). The meso-phenyl analogues, tetrakis(mesityl) porphyrins Ms-H (free-base) and Ms-Zn (Zinc) have been used as benchmarks to compare the UV-Vis absorption properties.…”