79015-49-9Relevant articles and documents
Acene Ring Size Optimization in Fused Lactam Polymers Enabling High n-Type Organic Thermoelectric Performance
Chen, Hu,Moser, Maximilian,Wang, Suhao,Jellett, Cameron,Thorley, Karl,Harrison, George T.,Jiao, Xuechen,Xiao, Mingfei,Purushothaman, Balaji,Alsufyani, Maryam,Bristow, Helen,De Wolf, Stefaan,Gasparini, Nicola,Wadsworth, Andrew,McNeill, Christopher R.,Sirringhaus, Henning,Fabiano, Simone,McCulloch, Iain
supporting information, p. 260 - 268 (2021/01/13)
Three n-type fused lactam semiconducting polymers were synthesized for thermoelectric and transistor applications via a cheap, highly atom-efficient, and nontoxic transition-metal free aldol polycondensation. Energy level analysis of the three polymers demonstrated that reducing the central acene core size from two anthracenes (A-A), to mixed naphthalene-anthracene (A-N), and two naphthalene cores (N-N) resulted in progressively larger electron affinities, thereby suggesting an increasingly more favorable and efficient solution doping process when employing 4-(2,3-dihydro-1,3-dimethyl-1H-benzimidazol-2-yl)-N,N-dimethylbenzenamine (N-DMBI) as the dopant. Meanwhile, organic field effect transistor (OFET) mobility data showed the N-N and A-N polymers to feature the highest charge carrier mobilities, further highlighting the benefits of aryl core contraction to the electronic performance of the materials. Ultimately, the combination of these two factors resulted in N-N, A-N, and A-A to display power factors (PFs) of 3.2 μW m-1 K-2, 1.6 μW m-1 K-2, and 0.3 μW m-1 K-2, respectively, when doped with N-DMBI, whereby the PFs recorded for N-N and A-N are among the highest reported in the literature for n-type polymers. Importantly, the results reported in this study highlight that modulating the size of the central acene ring is a highly effective molecular design strategy to optimize the thermoelectric performance of conjugated polymers, thus also providing new insights into the molecular design guidelines for the next generation of high-performance n-type materials for thermoelectric applications.
Coupled π-conjugated chromophores: Squaraine dye dimers as two connected pendulums
Kuster, Simon,Geiger, Thomas
, p. 110 - 116 (2014/11/07)
Intense absorption ability in the near infrared (NIR) region is mandatory for many technologies and applications. The design thereof is however quite complex since only a few dye classes show these properties. Polymeric squaraine dyes have them however they are mostly hardly soluble. Herein four dimeric soluble and easy to prepare squaraine dye dimers are reported with absorption maxima between 679 and 805 nm. The synthesis, characterisation, the determination of the physicochemical properties and the in silico study of the calculated molecular geometry, the molecular orbitals, and the calculated total charge density surface were compared. The coupling of the two chromophores is concluded as a matter of the distance in-between, the π-electron system of the bridge, the spatial orientation thereof, and the spatial orientation of the electronic transition moment. The closer the two chromophores were and the less out-of-plane elements the bridge has, the smaller the optical band gap is.
