查看更多>>摘要：? 2022 Elsevier B.V.Two-dimensional (2D) transition metal dichalcogenides (TMDs) materials have been applied in organic solar cells (OSCs), which possess excellent light transmittance, good charge carrier selectivity and high mobility. Herein, high quality 2D material of tungsten disulfide (WS2) nanosheets is synthesized by liquid exfoliation method, which is used to form a double-layer hole transport layer with soluble copper(I) thiocyanate (CuSCN). The introduction of WS2 nanosheets smooth the surface of CuSCN hole transport layers (HTL) and modify the interface between CuSCN HTL and light absorber. The cells using double-layer CuSCN/WS2 as HTL exhibit higher light photon utilization, weaker recombination loss compared to the reference cell with pristine CuSCN HTL. More importantly, it has been proved that the WS2 nanosheets act as intermedium between light absorbers and CuSCN, which contribute to efficient hole extraction process. As a result, a champion power conversion efficiency (PCE) of 9.00% is obtained in PTB7-Th:PC71BM light absorber based cell using CuSCN/WS2 as HTL, which is > 16% higher than the PCE of 7.75% achieved in reference cell with pristine CuSCN HTL. This result proves that 2D TMDs materials are promising candidates as charge selectivity for highly efficient solar cells.
查看更多>>摘要：? 2022Replacing the orthogonal molecular core in 2,2′,7,7′-Tetrakis[N,N-di(4-methoxyphenyl)amino]? 9,9′-spirobifluorene (spiro-OMeTAD) with π-conjugated functional group is a promising strategy for designing of dopant-free hole transport materials (HTMs) for perovskite solar cells (PSCs). Here, an organic molecule with 9-fluorenone core, namely TPA-9F (2,7-bis(4-(bis(4-methoxyphenyl)amino)phenyl)? 9 H-fluoren-9-one), which featuring with excellent intermolecualr and interlayer interaction, was successfully developed and applied in PSCs. It's found that TPA-9F shows multifunctional characteristics, such as close interlayer interaction with perovskite surface, strong hole transport capacity and hydrophobicity. As a result, mesoscopic n-i-p structured PSCs employing dopant-free TPA-9F as HTM exhibit a high efficiency of 18.40%, which is much higher than that using dopant-free spiro-OMeTAD (9.38%). This work demonstrate the great potential of π-conjugated functional group in designing efficient organic p-type semiconductors for dopant-free PSCs.
查看更多>>摘要：? 2022 Elsevier B.V.Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is the most researched conjugated polymer in the field of organic bioelectronics. The conjugated PEDOT backbone features good redox stability in aqueous electrolyte, and low oxidation potential. However, PEDOT:PSS has two major drawbacks. The PEDOT backbone lacks biofunctionality, limiting the fine tuning of its interface with the biological environment. The dopant PSS is insulating, resulting in a decrease in the capacitance of the polymer. Here, we describe the design of a random copolymer, P(EDOTCOOH-co-EDOTS), based on EDOT monomers functionalized with sulfonic and carboxylic acid groups. The copolymer was successfully synthesized by electropolymerization as confirmed by X-ray photoelectron spectroscopy. Contact angle measurements illustrated the high hydrophilicity of the P(EDOTCOOH-co-EDOTS) (28 ± 6o), attributed to the sulfonate group in the side chains. This in turn led to a higher water penetration into the copolymer film, enhancing significantly its volumetric capacitance (69 ± 4 F cm?3), and thereby, its performance when used as an active channel in an organic electrochemical transistor. Of note, we incorporated the sulfonate group in its sodium salt form retaining its highly ionized properties. This is the first instance of utilizing an uncapped, ionized sulfonate group covalently bound to the backbone of a polymer, where the resultant polymer is oxidized at very low potentials, as well as stable and electroactive in aqueous electrolytes. Furthermore, our molecular design to incorporate carboxylic acid groups paves the way for the development of conjugated polymers that can be tailored for bioelectronic applications.
查看更多>>摘要：? 2022 Elsevier B.V.Composite materials based on conducting polymers and transitional metal chalcogenides have attracted considerable attention as electrode materials for supercapacitors. Molybdenum disulfide is a layered transitional metal dichalcogenide extensively researched in energy storage and conversion applications, and poly(3,4-ethylenedioxythiophene) (PEDOT) is an intrinsically conducting polymer that can act as a conductive matrix. We propose a single-step electrochemical deposition of PEDOT/MoS2 composite materials from the dispersion containing commercially available MoS2 platelets and EDOT monomer. Potentiodynamic, galvanostatic, and potentiostatic modes are all suitable for synthesis of the materials with predominant content of MoS2, which is attached to the current collector via conducting PEDOT matrix. The materials can work in various water-based electrolytes and combine capacitor-like and redox pseudocapacitive response. The composites deposited on graphite foil in assembled asymmetric cells with Kynol carbon cloth counter-electrode deliver up to 870 mF cm?2 areal capacitance in LiClO4 aqueous solution at a current density of 1 mA cm?2 due to combined capacitive input of both components.
查看更多>>摘要：? 2022 Elsevier B.V.In this study, naphthalimide has been clicked with the N9- and C2-positions of carbazole, and two new monomers named KN and KC were synthesized, respectively. The fluorescent group naphthalimide and polymerizable group carbazole have been synthesized with Huisgen's 1,3-dipolar cycloaddition reaction in water environment by taking advantage of the linker ability of click chemistry to react easily and quickly. Monomers have been characterized via 1H NMR and FT-IR spectroscopy and electropolymerized in acetonitrile/boron trifluoride diethyl etherate (BFEE) by cyclic voltammetry technique. The electrochemically synthesized PKC has superior electrochemical and optical properties compared with PKN. Herein, the electron-rich nitrogen of the C2-substituted carbazole in PKC makes carbazole oxidation easier than the N9-substituted carbazole in PKN. Besides, another structural difference is the presence of the oxygen group in KC. This difference between the two structures is due to oxygen and nitrogen atom donating to the carbazole aromatic π system which increases the electron density in the carbazole.
查看更多>>摘要：? 2022 The AuthorsThe purpose of this study is to develop a planar field electron emission source that can be driven stably for a long time with low energy consumption and output power control to realize field-emission–cathodoluminescence (CL) devices with excellent energy efficiency. This was achieved driven by the motivation that the use of CLs with excellent quantum efficiency can create new values for society by realizing energy-saving lighting. We attempted to prepare dispersion coatings of highly crystalline single-walled carbon nanotubes (hc-SWCNTs) with guaranteed chemical stability by an industrial dispersion process. The change in chemical stability owing to the adoption of the dispersion process was traced by quantifying the shape of the thermogravimetric analysis (TGA) curve, and the process suitable for the dispersion of hc-SWCNTs was investigated. As a result, it was shown that the wet jet mill dispersion process could be combined to achieve dispersion with slightly deteriorated chemical stability. This was achieved by reducing the milling effect of foreign matter and by controlling the shear force and the number of shear cycles applied to the dispersion.
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