Electric double layer (EDL)-mediated transistors with ionic liquid (IL) gating have garnered substantial interest due to their exceptional properties, such as high transconductance and low-voltage operation, positioning them as promising candidates for organic electronics. In this study, we present an in situ measurement of effective gate bias voltage () in IL-gated organic field-effect transistors (IL-OFETs) using a modified current-voltage measurement configuration. The results reveal a significant deviation between and the applied gate bias (), indicating that the EDL at the gate/IL interface screens the applied voltage.
View Article and Find Full Text PDFFullerene adducts have attracted attention in a variety of applications including organic optoelectronic devices. In this regard, we have designed a covalently linked donor-acceptor dyad comprising a fluorobenzothiadiazole-thiophene (BTF-Th) unit with the electron acceptor fullerene in an Acceptor-Donor-Acceptor (A-D-A) molecular arrangement. We synthesized and characterized two new covalently bonded benzothiadiazole-based fullerene molecules, mono-adduct, 7 (benzothiadiazole : PCBM = 1 : 1, anchored terminally esterification reaction) and multi-adduct, 10-I (benzothiadiazole : PCBM = : 1, where ≥ 1, attached directly to the fullerene core the Prato reaction) using different synthetic strategies.
View Article and Find Full Text PDFWe successfully demonstrated a detailed and systematic enhancement of organic field effect transistors (OFETs) performance using dithienothiophene (DTT) and furan-flanked diketopyrrolopyrrole based donor-acceptor conjugated polymer semiconductor namely PDPPF-DTT as an active semiconductor. The self-assembled monolayers (SAMs) treatments at interface junctions of the semiconductor-dielectric and at the semiconductor-metal electrodes has been implemented using bottom gate bottom contact device geometry. Due to SAM treatment at the interface using tailored approach, the significant reduction of threshold voltage (V) from - 15.
View Article and Find Full Text PDFThe hole and electron extracting interlayers in the organic solar cells (OSCs) play an important role in high performing devices. The present work focuses on an investigation of Zinc oxide/bulk heterojunction (ZnO/BHJ) and BHJ/MoO (Molybdenum oxide) buried planar interfaces in inverted OSC devices using the optical contrast in various layers along with the electrical measurements. The x-ray reflectivity (XRR) analysis demonstrates the formation of additional intermixing layers at the interfaces of ZnO/BHJ and BHJ/MoO .
View Article and Find Full Text PDFTwo polymers based on (3,7)-3,7-bis(2-oxoindolin-3-ylidene)benzo[1,2-:4,5-']difuran-2,6(3,7)-dione (BIBDF) coupled with ()-2-(2-(thiophen-2-yl)vinyl)thiophene (TVT) or dithienylbenzothiadiazole (TBT), namely PBIBDF-TVT and PBIBDF-TBT were synthesized the Stille coupling reaction. The effect of benzothiadiazole or vinylene-π spacer of the copolymers on optical properties, energy levels, electronic device performance and microstructure were studied. It was found that PBIBDF-TBT based OFET devices, annealed at 180 °C, showed better performance with the highest electron mobility of 2.
View Article and Find Full Text PDFHomeopathy
August 2018
Background: Acute encephalitis syndrome (AES) is endemic to certain parts of India, with limited treatment options. In our initial exploratory comparative observational study of 151 patients with AES, there was significantly reduced mortality with adjunctive homeopathy compared to institutional management protocol (IMP). The present randomized placebo-controlled trial brings more statistical rigor to this research program.
View Article and Find Full Text PDFLow-energy linear absorption spectrum of a series of 48 donor-acceptor-donor (D-A-D) scheme based thiophone-benzo(bis-)X-diazole molecules with X = O, S, Se, or Te are calculated using time dependent density functional theory in order to propose strategical design of molecules that can efficiently absorb light in the infrared and visible region of the solar spectrum. Our study establishes that optical properties of the D-A-D based organic molecules significantly depend on the donor-to-acceptor (D/A) ratio and the strength of the acceptor moiety. Thus, by choice of a suitable D/A ratio and type of the acceptor moiety, the linear absorption spectrum can be largely shifted, in general, while the optical gap can be engineered over a wide energy range of ∼0.
View Article and Find Full Text PDFPhys Chem Chem Phys
October 2013
A benzothiadiazole end-capped small molecule 3,6-bis(5-(benzo-[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-2,5-bis(2-butyloctyl)pyrrolo-[3,4-c]pyrrole-1,4(2H,5H)-dione (BO-DPP-BTZ) using a fused aromatic moiety DPP (at the centre) is designed and synthesized. BO-DPP-BTZ is a donor–acceptor–donor (D–A–D) structure which possesses a band gap of 1.6 eV and exhibits a strong solid state ordering inferred from ~120 nm red shift of the absorption maxima from solution to thin film.
View Article and Find Full Text PDFChem Commun (Camb)
August 2012
Furan substituted diketopyrrolopyrrole (DBF) combined with benzothiadiazole based polymer semiconductor PDPP-FBF has been synthesized and evaluated as an ambipolar semiconductor in organic thin-film transistors. Hole and electron mobilities as high as 0.20 cm(2) V(-1) s(-1) and 0.
View Article and Find Full Text PDFA new diketopyrrolopyrrole (DPP)-containing donor-acceptor polymer, poly(2,5-bis(2-octyldodecyl)-3,6-di(furan-2-yl)-2,5-dihydro-pyrrolo[3,4-c]pyrrole-1,4-dione-co-thieno[3,2-b]thiophene) (PDBF-co-TT), is synthesized and studied as a semiconductor in organic thin film transistors (OTFTs) and organic photovoltaics (OPVs). High hole mobility of up to 0.53 cm(2) V(-1) s(-1) in bottom-gate, top-contact OTFT devices is achieved owing to the ordered polymer chain packing and favoured chain orientation, strong intermolecular interactions, as well as uniform film morphology of PDBF-co-TT.
View Article and Find Full Text PDFA donor-acceptor polymer semiconductor, PDQT, comprising diketopyrrolopyrrole (DPP) and β-unsubstituted quaterthiophene (QT) for organic thin film transistors (OTFTs) is reported. This polymer forms ordered layer-by-layer lamellar packing with an edge-on orientation in thin films even without thermal annealing. The strong intermolecular interactions arising from the fused aromatic DPP moiety and the DPP-QT donor-acceptor interaction facilitate the spontaneous self-assembly of the polymer chains into close proximity and form a large π-π overlap, which are favorable for intermolecular charge hopping.
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