11. Conjugated polymer mesocrystals with structural and optoelectronic coherence and anisotropy in three dimensionsLiyang Yu, Egon Pavlica, Ruipeng Li, Yufei Zhong, Carlos Silva, Gvido Bratina, Christian Műller, Aram Amassian, Natalie Stingelin, 2022, izvirni znanstveni članek Ključne besede: organic semiconductor, time-of-flight, charge carrier mobility, solid processing, large crystal Objavljeno v RUNG: 28.02.2023; Ogledov: 1130; Prenosov: 82 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
12. Solution-processed graphene-nanographene van der Waals heterostructures for photodetectors with efficient and ultralong charge separationZhaoyang Liu, Haixin Qiu, Shuai Fu, Can Wang, Xuelin Yao, Alex Dixon, Stéphane Campidelli, Egon Pavlica, Gvido Bratina, Sheng Zhao, Loïc Rondin, 2021, izvirni znanstveni članek Ključne besede: absorption, colloids, molecules, sensors, two dimensional materials Objavljeno v RUNG: 28.02.2023; Ogledov: 1202; Prenosov: 0 |
13. Influence of P3HT:PCBM ratio on thermal and transport properties of bulk heterojunction solar cellsDorota Korte, Egon Pavlica, Domen Klančar, Gvido Bratina, Michal Pawlak, Ewa Gondek, Peng Song, Junyan Liu, B. Derkowska-Zielińska, 2023, izvirni znanstveni članek Ključne besede: organic bulk-heterojunction solar cells, polymer-fullerene solar cells, photothermal beam deflection spectrometry, non-radiative recombination, thermal diffusivity, frequency domain methods Objavljeno v RUNG: 09.01.2023; Ogledov: 1638; Prenosov: 19 Celotno besedilo (2,58 MB) Gradivo ima več datotek! Več... |
14. Photoexcited charge mobility in quasi two-dimensional polyacetyleneNadiia Pastukhova, Kejun Liu, Renhao Dong, Gvido Bratina, Xinliang Feng, Egon Pavlica, 2022, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Two-dimensional conjugated polymers (2DCPs) have been described and recognised as crystalline, one- to two-layer polymer nanosheets prepared by 2D covalent polymerization exhibiting strong in-plane π-electron delocalization with two orthogonal directions and weak out-of-plane π-π stacking.[1,2] The extension of polymer dimensionality into two dimensions improves the alignment of individual polymer sheets and overcomes the limitations associated with charge carrier hopping between polymer chains in one-dimensional and crosslinked polymers.[3] Compared to other two-dimensional materials such as graphene or transition metal dichalcogenides, 2DCPs offer a high degree of flexibility in chemical design and are compatible with liquid-based processing methods. Various 2DCPs have been synthesised by surfactant monolayer-assisted interfacial synthesis (SMAIS).[5]
Of particular interest is the photoresponse of these materials due to their tunable properties, such as bandgap and associated wavelength-dependent photoexcitation, which enables a wide range of applications in optoelectronic devices. Using time-of-flight photoconductivity (TOF-PC) measurements [4], we investigate the charge transport properties of 2D polyacetylene prepared by SMAIS method. We preform TOF-PC measurement of 2D polyacetylene using a focused nanosecond pulse laser at 325 nm and electrode separation of 250 µm. From the bias polarity and time duration of the photocurrent, we can determine the polarity, velocity and mobility of photoexcited charge carriers as a function of applied bias voltage and excitation wavelength. Using excitation at 325 m, we observed an electron mobility in the range of 150 cm2 V-1 s-1, which is in the realm of most advances small-molecule single-crystal organic semiconductors and almost an order of magnitude higher than linear polymeric semiconductors. Ključne besede: Two-dimensional conjugated polymers, 2DCPs, 2Dpolymers, charge mobility, time-of-flight photoconductivity Objavljeno v RUNG: 29.11.2022; Ogledov: 1188; Prenosov: 0 Gradivo ima več datotek! Več... |
15. Enhancement of indacenodithiophene–benzothiadiazole copolymer field-effect mobility with MXenesJurij Urbančič, Nadiia Pastukhova, Manisha Chhikara, Hu Chen, Iain Mcculloch, Huanhuan Shi, Ali Shaygan Nia, Xinliang Feng, Egon Pavlica, Gvido Bratina, 2022, objavljeni povzetek znanstvenega prispevka na konferenci Opis: The predominant mode of charge carrier transport in thin layers of organic semiconductors (OSs) is thermally-activated hopping between localized states. This results in lower charge mobility compared to inorganic semiconductors precluding the use of OSs in high-speed electronic devices. Therefore, significant effort is invested to improve charge carrier mobility of OS thin layers, which form the basis of most of the organic electronic devices. Recent advances in the field of two-dimensional (2D) materials stimulated their use as addition to OS thin layers to boost the charge carrier mobility. MXenes promise to deliver most of the benefits of 2D materials coupled with large scale fabrication capability. Herein we examined Ti3C2X (X is O or OH group termination) MXene, as a candidate to improve charge carrier mobility in thin layer of indacenodithiophene-co-benzothiadiazole (IDTBT), a polymer exhibiting high electron mobility in defect-free crystalline layers. In our work we demonstrate that improvement in electron mobility in solution-cast IDTBT thin layers can be achieved by depositing a non-connected network of MXene flakes at the gate-dielectric/IDBT interface. Bottom-gate field-effect transistors (FETs) comprising of Au electrodes on n-doped silicon wafer covered with 230 nm of thermally deposited SiO2 were prepared and characterized. Charge carrier mobilities determined from transfer characteristics of FETs composing neat IDTBT channels were found to be in the range of 1 - 2×10−2 cm2/Vs. Devices comprising MXene flakes at the interface between SiO2 and IDTBT, instead exhibited a factor of four increase in electron mobility, while preserving the on/off ratio of 104. Ključne besede: MXene, IDTBT, charge carrier mobility, OFET Objavljeno v RUNG: 20.10.2022; Ogledov: 1400; Prenosov: 10 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
16. Electrochemical ZnO-based impedimetric sensor for aqueous ammonia detection for precision animal agricultureKateryna Vyshniakova, Huiwen Bai, Victor Marco Rocha Malacco, Egon Pavlica, Richard M. Voyles, Shawn S. Donkin, Amanda Gehman, Robert A. Nawrocki, 2021, objavljeni povzetek znanstvenega prispevka na konferenci Ključne besede: electrochemical impedance spectroscopy, mixed conduction, organic sensor Objavljeno v RUNG: 07.06.2021; Ogledov: 2296; Prenosov: 37 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
17. Impedimetric detection of histamine using PEDOT:PSS-based organic electrochemical sensor for precision animal agricultureHuiwen Bai, Kateryna Vyshniakova, Egon Pavlica, Victor Marco Rocha Malacco, Alexandros Yiannikouris, Thirupathi Reddy Yerramreddy, Richard M. Voyles, Shawn S. Donkin, Robert A. Nawrocki, 2021, objavljeni povzetek znanstvenega prispevka na konferenci (vabljeno predavanje) Ključne besede: electrochemical impedance spectroscopy, mixed conduction Objavljeno v RUNG: 07.06.2021; Ogledov: 2103; Prenosov: 37 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
18. Multiresponsive nonvolatile memories based on optically switchable ferroelectric organic field-effect transistorsMarco Carroli, Alex Dixon, Martin Herder, Egon Pavlica, Stefan Hecht, Gvido Bratina, Emanuele Orgiu, Paolo Samorì, 2021, izvirni znanstveni članek Opis: Organic transistors are key elements for flexible, wearable, and biocompatible logic applications. Multiresponsivity is highly sought‐after in organic electronics to enable sophisticated operations and functions. Such a challenge can be pursued by integrating more components in a single device, each one responding to a specific external stimulus. Here, the first multiresponsive organic device based on a photochromic–ferroelectric organic field‐effect transistor, which is capable of operating as nonvolatile memory with 11 bit memory storage capacity in a single device, is reported. The memory elements can be written and erased independently by means of light or an electric field, with accurate control over the readout signal, excellent repeatability, fast response, and high retention time. Such a proof of concept paves the way toward enhanced functional complexity in optoelectronics via the interfacing of multiple components in a single device, in a fully integrated low‐cost technology compatible with flexible substrates. Ključne besede: organic transistors, memory, time-dependent Objavljeno v RUNG: 11.03.2021; Ogledov: 2277; Prenosov: 0 Gradivo ima več datotek! Več... |
19. Impedimetric, PEDOT:PSS-based organic electrochemical sensor for detection of histamine for precision animal agricultureHuiwen Bai, Kateryna Vyshniakova, Egon Pavlica, Victor Marco Rocha Malacco, Alexandros Yiannikouris, Thirupathi Reddy Yerramreddy, Shawn S. Donkin, Richard M. Voyles, Robert A. Nawrocki, 2020, izvirni znanstveni članek Ključne besede: organic semiconductors, biosensor, electrochemical transistor Objavljeno v RUNG: 18.02.2021; Ogledov: 2483; Prenosov: 142 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
20. A pyrrolopyridazinedione-based copolymer for fullerene-free organic solar cellsAstrid-Caroline Knall, Samuel Rabensteiner, Sebastian F. Hoefler, Matiss Reinfelds, Mathias Hobisch, Heike M. A. Ehmann, Nadiia Pastukhova, Egon Pavlica, Gvido Bratina, Illie Hanzu, Shuguang Wen, Renqiang Yang, Gregor Trimmel, Thomas Rath, 2021, izvirni znanstveni članek Opis: The recent success of non-fullerene acceptors in organic photovoltaics also entails a change in the requirements to the polymer donor in terms of optical and morphological properties leading to a demand for novel conjugated polymers. Herein, we report on the synthesis of a 1,4-bis-(thiophene-2-yl)-pyrrolopyridazinedione based copolymer with 2-ethylhexyl substituents on the pyrrolopyridazinedione moiety. A 2D conjugated benzodithiophene (BDT) was chosen as comonomer. The resulting copolymer T-EHPPD-T-EHBDT showed a molecular weight of 10.2 kDa, an optical band gap of 1.79 eV, a hole mobility of 1.8 × 10−4 cm2 V−1 s−1 and a preferred face-on orientation with regard to the substrate. The comparably wide band gap as well as the determined energy levels (HOMO: −5.47 eV, LUMO: −3.68 eV) match well with the narrow band gap non-fullerene acceptor ITIC-F, which was used as the acceptor phase in the bulk heterojunction absorber layers in the investigated solar cells. The solar cells, prepared in inverted architecture, revealed power conversion efficiencies up to 7.4% using a donor:acceptor ratio of 1 : 1 in the absorber layer. Ključne besede: non-fullerene solar cells, charge transport, charge mobility, power conversion efficiency Objavljeno v RUNG: 27.01.2021; Ogledov: 2760; Prenosov: 0 Gradivo ima več datotek! Več... |