NIR-sensing ambipolar organic phototransistors with conjugated terpolymer layers based on diketopyrrolopyrrole-benzothiadiazole-naphthalenediimide comonomer units

Abstract

Here we report ambipolar organic phototransistors (OPTRs), which can be operated in both p-channel and n-channel modes, with sensing channel layers of a conjugated terpolymer, poly[4-(5-(4-(5-(6-methoxy-7-methyl-5-(octyloxy)benzo[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-2-(2-methyldodecyl)-5-(2-octyldodecyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrol-1-yl)thiophen-2-yl)-9-methyl-2,7-bis(2-octyldodecyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone] (PDPP-8OBT-NDI) that was synthesized...

Conjugated Polymer Heteroatom Engineering Enables High Detectivity Symmetric Ambipolar Phototransistors

“…OPTs exhibited increased photocurrent upon light illumination (905 nm) in both p and n‐type regimes, with responsivity in the order of around 1 mA W⁻ 1 . [ 28 ] The BHJ‐based approach has also been demonstrated from PCBM and a DPP‐based polymer blend for unipolar NIR OPTs. Blending was found to reduce charge trapping and recombination with OPTs exhibiting a responsivity of 32.5 A W⁻ 1 and photosensitivity of 0.8 × 10 4 under 870 nm light illumination.…”

Elucidating the effects of the sidechain substitution direction on the optoelectronic properties of isomeric diketopyrrolopyrrole-based conjugated polymers for near-infrared organic phototransistors

“…Thus, they can be applied in NIR phototransistors (OPTs), which can convert NIR light into electrical signals to realize the detection of NIR light. 2,[7][8][9] Although D-A copolymers have been intensively investigated in photodetector applications, [10][11][12][13][14] there are only a handful of instances that can achieve high NIR-OPT performances.…”

Copolymers Based on π-Conjugated Asymmetric Naphthalene Diimide Building Blocks: Synthesis, Crystallography, and Structure–Property–Charge Transport/Photovoltaic Correlations

“…N-type (electron-transporting) conjugated polymers are essential components in diverse organic optoelectronic device technologies − such as all-polymer solar cells (APSCs), − thermoelectric generators, − n-type organic field-effect transistors (OFETs), , and others, , and for these reasons have been extensively studied over the past two decades. − N-type polymers based on the naphthalene diimide ( NDI ) acceptor unit are among the most investigated with poly­[ N , N ′-bis­(2-octyldodecyl)-naphthalene-1,4,5,8-bis­(dicarboximide)-2,6-diyl]- alt -5,5′-(2,2′-bithiophene) ( PNDITh2 or N2200 ) being the most prominent example, exhibiting an impressive electron mobility surpassing 6 cm 2 /(V s), low energetic disorder, and enabling APSC power conversion efficiencies >10%. − Since N2200 exhibits an important optoelectronic performance, several NDI -based donor–acceptor (D-A) copolymers with regioregular (RR) and regioirregular (RI) architectures have been developed. − However, NDI polymers achieved via/comprising an asymmetric NDI building block have not been reported to date due to limited synthetic protocols . Asymmetric structures generate local dipoles that can enhance interactions between neighboring molecules, hence favoring charge transport − as well as photovoltaic performance for several organic semiconductors. − Conventional Stille polycondensation reactions using dibrominated NDI building blocks and bis­(trialkylstannyl) aryl units as the starting materials have been the primary synthetic method for preparing NDI polymers; however, this approach is not particularly sustainable and using two symmetric building blocks only generates symmetric NDI polymers. , Kiriy and co-workers have developed an effective alternative polymerization protocol in which 2,6-di­(bromoaryl) substituted NDI units (Br-Het- NDI -Het-Br) are polymerized using activated zinc, which avoids the use of toxic stannanes.…”