Ladder‐Like Difluoroindacenodithiophene‐4,9‐dione Derivative: A New Acceptor System for High‐Mobility n‐Type Polymer Semiconductors

Abstract

Ladder-like aromatic diketones (LADK), which possess a coplanar π-extended geometry, a high electron deficiency as well as various attractive optoelectronic properties, are demonstrated as the promising candidates in building small-molecule organic electron-transporting materials, yet reports on direct integration of these structural motifs into n-type polymers are rarely accessed. Herein, it is demonstrated that a possibility of realizing unipolar n-type characteristics of such acceptor system by developing two novel donor-acceptor type polymers, in which the newly developed LADK unit, named as 3,8-bis(2-decyltetradecyl)-5,10-difluoro-s-indaceno[1,2-b:5,6-b′] dithiophene-4,9-dione (FIDTO-R), is adopted as the acceptor segments. The resulting polymers present deep-lying unoccupied molecular orbital levels (as low as −3.84 eV), compact π-π stacking (d-spacing, ≈3.57 Å) coupled with uniform nanofiber-like surface morphology. All these factors contribute to excellent unipolar n-type characteristics with high electron mobilities of 0.27 and 1.01 cm 2 V −1 s −1 , together with high inverter gain values of 141 and 80, respectively. The recorded values are among the best in n-type polymer field-effect transistors and associated inverter circuits. These findings unambiguously reveal that the as-prepared FIDTO-R and its analog LADK derivatives are another type of excellent building blocks for the construction of high-mobility n-type polymers.

Electron-Transporting Conjugated Polymers from Novel Aromatic Five-Membered Diimides: Naphtho[1,2-b:4,3-b′]-dithiophene and -Diselenophene Diimides

“…In combination with the DSC above result, 2D-GXRD and AFM data reveal that the films of P1–P4 are in amorphous-like state. This amorphous-like morphology and microstructure can be associated with the weak intermolecular interactions between the polymer chains, potentially leading to the unsatisfactory intermolecular charge transport as relative to the most of crystalline-like conjugated polymers. , …”

Structure‐Property Relationship of Conjugated Polymers Utilizing Isomerized Fused Benzothiadiazole‐Based Building Blocks†

“…[ 13‐15 ] Many donor and acceptor building blocks have been developed to construct D‐A type conjugate polymers. [ 16‐20 ] Amongst these building blocks, benzothiadiazole (BTz) is widely used in the construction of high‐performance D‐A type conjugated polymers due to its merits of rigid planar structure, electron deficiency and structural modifiability. [ 21‐22 ] For example, conjugated polymers obtained by copolymerization of benzothiadiazole with indacenodithiophene (IDT), cyclopentadithiophene (CPDT), diketopyrrolopyrrole (DPP) have achieved high‐performance in OPVs and OFETs devices.…”

Synthesis and charge-transport properties of novel π-conjugated polymers incorporating core-extended naphtho[2,1-b:3,4-b′]dithiophene diimides

“…1 Modification of classic A units 8–16 [ e.g. , naphthalene diimide (NDI) and perylene diimide (PDI)] or the creation of novel A systems, 17–26 therefore, has recently become a popular subject of engineering the optoelectronic properties of CPSs.…”