Versatile α,ω‐Disubstituted Tetrathienoacene Semiconductors for High Performance Organic Thin‐Film Transistors

Abstract

Facile one‐pot [1 + 1 + 2] and [2 + 1 + 1] syntheses of thieno[3,2‐b]thieno[2′,3′:4,5]thieno[2,3‐d]thiophene (tetrathienoacene; TTA) semiconductors are described which enable the efficient realization of a new TTA‐based series for organic thin‐film transistors (OTFTs). For the perfluorophenyl end‐functionalized derivative DFP‐TTA, the molecular structure is determined by single‐crystal X‐ray diffraction. This material exhibits n‐channel transport with a mobility as high as 0.30 cm2V−1s−1 and a high on‐off ratio of 1.8 × 107. Thus, DFP‐TTA has one of the highest electron mobilities of any fused thiophene semiconductor yet discovered. For the phenyl‐substituted analogue, DP‐TTA, p‐channel transport is observed with a mobility as high as 0.21 cm2V−1s−1. For the 2‐benzothiazolyl (BS‐) containing derivative, DBS‐TTA, p‐channel transport is still exhibited with a hole mobility close to 2 × 10−3 cm2V−1s−1. Within this family, carrier mobility magnitudes are strongly dependent on the semiconductor growth conditions and the gate dielectric surface treatment.

Bicyclopentadithiophene-Based Organic Semiconductor for Stable and High-Performance Perovskite Solar Cells Exceeding 22%

“…The DPV data clearly confirms that the variation in the alkyl chain (branched octyl vs linear octyl) has no significant effect on the electrochemical properties of NFAs, and each pair possesses similar oxidation and reduction potentials. , In contrast, halogenated compounds 2 and 3 feature more positive oxidation ( E ox = +1.23 V) and reduction ( E red = −0.28 V) potentials in comparison to their analogue 1 ( E ox = +1.17 V, E red = −0.40 V), which leads to lower HOMO (−5.67 eV) and LUMO (−4.16 eV) vs seen with nonhalogenated 1 [HOMO (−5.61 eV) and LUMO (−4.04 eV)]. Due to the electron-deficient nature of the halogenated indanones, compounds 2 and 3 display a shift toward higher values in both oxidation and reduction potentials in comparison to the potentials noticed for 1 . ,, In particular, the LUMO levels of halogenated NFAs ( 2 and 3 ) are much lower than those of nonhalogenated ones ( 1 ), comparing the difference in HOMO levels, resulting in the energy gap contractions of NFAs 2 and 3 compared to 1 . Consequently, the narrower energy gaps were confirmed for the halogenated 2 – 3 (∼1.50 eV) vs 1 (1.56 eV), which is in line with their optical energy gap values: 2 – 3 (∼1.44 eV) < 1 (1.49 eV).…”

“…Due to the electron-deficient nature of the halogenated indanones, compounds 2 and 3 display a shift toward higher values in both oxidation and reduction potentials in comparison to the potentials noticed for 1 . 56 , 59 , 60 In particular, the LUMO levels of halogenated NFAs ( 2 and 3 ) are much lower than those of nonhalogenated ones ( 1 ), comparing the difference in HOMO levels, resulting in the energy gap contractions of NFAs 2 and 3 compared to 1 . Consequently, the narrower energy gaps were confirmed for the halogenated 2 – 3 (∼1.50 eV) vs 1 (1.56 eV), which is in line with their optical energy gap values: 2 – 3 (∼1.44 eV) < 1 (1.49 eV).…”

Highly Efficient Indoor Organic Solar Cells by Voltage Loss Minimization through Fine-Tuning of Polymer Structures

“…Since the (010) peak corresponds to the OOP pi−pi stacking of the polymer backbone, the smaller d-spacings for WF3S (3.70Å) and WF3F (3.67Å) as compared to WF3 (3.73Å) confirm that the presence of the sulfur atoms at the alkylthio side groups of WF3S and the fluoro atoms at the thienyl side groups of WF3F enables strong intermolecular noncovalent interactions. 44,51,52 In addition, all polymers show a weak (002) diffraction peak in the IP at q ∼ 0.665 Å −1 (d = 9.45 Å), which is equivalent to half of the unit length of the polymer backbone (18.5 Å). A full width at half-maximum of the scattering peak represents the coherence length in crystals, which can be calculated using the Scherrer equation.…”

Tackling Solubility Issues in Organic Synthesis: Solid-State Cross-Coupling of Insoluble Aryl Halides

“…Under the high-temperature ball-milling conditions, the reactions were significantly accelerated and were completed within 5 min to give the desired products ( 3b – e ) in excellent yield ( 3b , 98%; 3c , 98%; 3d , 98%; 3e , 99%). Notably, this solid-state reaction permitted the rapid construction of dithienothiophene derivatives ( 3f ), a core structure frequently found in light harvesters for dye-sensitized solar cells (80%, 60 min). − …”