Regulation of the backbone structure and optoelectrical properties of bis-pyridal[2,1,3]thiadiazole-based ambipolar semiconducting polymers via a fluorination strategy

Abstract

Polymer semiconductors with coplanar, π-extended confirmation and high electron affinity are regarded as the promising candidates for high-mobility ambipolar organic field-effect transistors. Herein a highly electron-deficient, coplanar, π-extended bis-pyridal[2,1,3]thiadiazole (BPT)...

Non-covalent interactions (NCIs) in π-conjugated functional materials: advances and perspectives

“…As expected, 48a exhibited higher electron mobility than 48b owing to the difference in structure (S⋯O interlock and π–π stacking in 48a ). Liu and co-workers 100 noted that the backbone co-planarity, electronic properties, film organization and the CT properties of semiconducting polymers could be largely modulated by fluorination strategy, which led to weak F⋯S non-covalent conformation lock. An ambipolar device based on 49a (Chart 6) ( μ h / μ e = 0.332/1.602 cm 2 V −1 s −1 ) showed better performance than the non-fluorinated counterpart 49b ( μ h / μ e = 0.0135/0.0191 cm 2 V −1 s −1 ) attributed to enhanced backbone co-planarity and fluorine substitutes.…”

Synthetic strategies, molecular engineering and applications of semiconducting polymers based on diarylethylene units in electronic devices

“…Among the reported acceptor building blocks, a series of thiadiazole derived π-electron cores have been used to develop high-performance semiconducting polymers, such as BT, 148 benzo[2,1,3]triazole (BTz), 149 naphthobis[1,2,5]thiadiazole (NT), 150 and bis-pyridal[2,1,3]thiadiazole (BPT) 151. BT is one of the most representative acceptor units with simplest molecular structures in thiadiazole derivatives.…”

Copolymers Containing 1-Methyl-2-phenyl-imidazole Moieties as Permanent Dipole Generating Units: Synthesis, Spectroscopic, Electrochemical, and Photovoltaic Properties

“…In the majority of cases, they are low band gap semiconductors exhibiting appropriate ionization potential (IP) and electron affinity (EA) values to assure their ambipolarity. As a result, they can serve as components of active layers in various types of ambipolar organic field-effect transistors, characterized by well-balanced n-type and p-type electrical transport [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Low ionization potential (IP) and high electron affinity (EA) of D–A and D–A–D polymers, together with the presence of several chromophore groups, promote their reversible electrochemical and spectroelectrochemical behavior [ 16 ].…”