- 标题
- 摘要
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- 实验方案
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Electrochromic 2,4,6-triphenyl-1,3,5-triazine based esters with electron donor-acceptor structure
摘要： Ten tripod-shaped electrochromic materials (compound 1–10) were designed and synthesized by esterification of 4,4',4''-s-triazine-2,4,6-triyl-tribenzoic acid with different alcohols and phenols. These materials have a 2,4,6-triphenyl-1,3,5-triazine core and three ester side arms, forming an electron donor–π-acceptor structure. The electrochemical and optical properties of 1–10 were characterized by cyclic voltammetry and ultraviolet–visible spectroelectrochemistry. The conjugated structure of 1–10 markedly influenced their electrochemical properties. Electrochromic devices containing some of these compounds (1, 2, 4, 5, and 10) displayed intense color changes, fast switching times (<2 s), high optical contrast (>60%), good switching stability, high optical density (>1.0), and high coloring efficiency (>1000 cm2 C?1). The colored state of these devices strongly depended on the conjugated structure of the tripod-shaped component. Short chain lengths (compounds 1 and 2) and electron-donating groups (compounds 4, 5, 8, and 10) were beneficial to electrochromic properties, whereas a longer chain length (compound 3) and electron-withdrawing groups (compounds 6 and 9) adversely affected electrochromic properties.
关键词： Electron donor-acceptor structure,2,4,6-Triphenyl-1,3,5-triazine based esters,Tripod-shaped electrochromic materials,Electrochromic devices
更新于2025-09-23 15:23:52
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Ternary copolymerization strategy reducing the cost of benzodithiophenea??benzodithiophenedione polymer, retaining high photovoltaic performance
摘要： The photovoltaic performance of organic solar cells has been rapidly improved. However, in actual production and application, there are still many challenges for organic photovoltaic devices and one of the important strategies to facilitate industrialization is reducing material price. The BDT-BDD binary copolymer donor material has good photovoltaic performance. However, the high price of benzodithiophenedione (BDD) monomer limits its industrialization. In contrast, benzotriazole (BTA) monomers with lower price possess an enormous potential to solve this problem. Therefore, in this paper, it is reported that the synthesis of ternary copolymerization by adding BTA units into BDT-BDD copolymer with two different acceptor units. Through research, it is found that such a strategy can effectively reduce the price of BDT-BDD polymer, and increasing the content of BTA units in polymer to reduce the content of expensive BDD units can still retain the excellent photovoltaic properties of BDT-BDD polymer. When only 20 mol % of BDD units remained, the bulk-heterojunction (BHJ) structure with the synthesized donor polymer and acceptor ITIC can achieve an open circuit voltage of 0.913 V with a short circuit current of 16.87 mA cm-2 and 9.12% maximum photoelectric conversion efficiency, which is much cheaper than BDT-BDD polymer, in terms of structural units. Therefore, the results show that the addition of BTA can effectively reduce the material cost (vs. BDD only) while retaining the good photovoltaic properties of the material, and has a certain guiding effect on the commercialization of OSC.
关键词： electron donor materials,ternary copolymer,optical properties,low-cost donor materials
更新于2025-09-23 15:21:01
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Novel Heteroleptic Ruthenium(II) Complexes with 2,2a?2- Bipyridines Containing a Series of Electron-Donor and Electron-Acceptor Substituents in 4,4a?2-Positions: Syntheses, Characterization, and Application as Sensitizers for ZnO Nanowire-Based Solar Cells
摘要： A novel series of complexes of the formula [Ru(4,4′-X2-bpy)2(Mebpy-CN)](PF6)2 (X = ?CH3, ?OCH3, ?N(CH3)2; Mebpy-CN = 4-methyl-2,2′-bipyridine-4′-carbonitrile) have been synthesized and characterized by spectroscopic, electrochemical, and photophysical techniques. Inclusion of the electron-withdrawing substituent ?CN at one bpy ligand and di?erent electron-donor groups ?X at the 4,4′-positions of the other two bpy ligands produce a ?ne tuning of physicochemical properties. Redox potentials, electronic absorption maxima, and emission maxima correlate well with Hammett’s σ p parameters of X. Quantum mechanical calculations are consistent with experimental data. All the complexes can be anchored through the nitrile moiety of Mebpy-CN over ZnO nanowires in dye-sensitized solar cells that exhibit an improvement of light to electrical energy conversion e?ciency as the electronic asymmetry increases in the series.
关键词： Electron-donor and Electron-acceptor substituents,Ruthenium(II) complexes,ZnO nanowire-based solar cells,Dye-sensitized solar cells,2,2′-Bipyridines
更新于2025-09-23 15:19:57
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Synergy of light harvesting and energy transfer as well as short-range charge shift reactions in multicomponent conjugates
摘要： We report herein on the design, the synthesis, and the characterization of a panchromatic, charge stabilizing electron donor–acceptor conjugate: (BBPA)3–ZnPor–ZnPc–SubPc 1. Each component, that is, bis(biphenyl)phenylamine (BBPA), Zn(II) porphyrin (ZnPor), Zn(II) phthalocyanine ZnPc, and subphthalocyanine (SubPc), has been carefully chosen and modified to enable a cascade of energy and charge transfer processes. On one hand, ZnPor, has been functionalized with three electron-donating BBPA as primary and secondary electron donors and to stabilize the final charge-separated state, and, on the other hand, a perfluorinated SubPc has been selected as ultimate electron acceptor. In addition, the ZnPc unit contains several trifluoromethylphenyl moieties to match its energy levels to those of the other components. In fact, irradiation of the heteroarray 1 triggers a cascade of light harvesting across the entire visible range, unidirectional energy transfer, exergonic charge separating, and short-range charge shifting to afford a (BBPA)3(cid:129)+–ZnPor–ZnPc–SubPc(cid:129)? charge-separated state. The lifetime of the latter reaches well into the range of tens of nanoseconds with a 14% quantum yield.
关键词： charge stabilizing,light harvesting,panchromatic,charge transfer,energy transfer,porphyrinoids,electron donor–acceptor conjugate
更新于2025-09-19 17:15:36
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Synthesis of the diketopyrrolopyrrole/terpyridine substituted carbazole derivative based polythiophenes for photovoltaic cells
摘要： A series of conjugated polythiophenes (PTs) having low band gap energies (PDPP, PDPCz21, PDPCz11), with 2-ethylhexyl-functionalized 2,5-thienyl diketopyrrolopyrrole (TDPP) as the electron acceptor and terpyridine-substituted carbazole (TPCz) as the electron donor, have been synthesized and studied for their applicability in polymer-based photovoltaic cells (PVCs). The thermal stability and solvent solubility of PTs increased upon increasing the content of the TPCz derivative. PVCs were fabricated having the following architecture: indium tin oxide/poly(3,4-ethylenedioxythiophene):polystyrenesulfonate/PT:6,6-phenyl-C71-butyric acid methyl ester (PC71BM)/Ca/Ag. The compatibility between the PT and PC71BM improved upon increasing the TPCz content. The photovoltaic properties of the PDPCz21-based PVCs were superior to those of their PDPP- and PDPCz11-based counterparts.
关键词： electron donor,photovoltaic cells,diketopyrrolopyrrole,electron acceptor,conjugated polythiophenes,terpyridine-substituted carbazole
更新于2025-09-19 17:13:59
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Highly efficient exciplex-based OLEDs incorporating a novel electron donor
摘要： Highly Efficient Exciplex-Based OLEDs Incorporating a Novel Electron Donor
关键词： exciplex,phosphorescent,electron donor,TADF,OLEDs
更新于2025-09-19 17:13:59
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A distorted lactam unit with intramolecular hydrogen bonds as the electron donor of polymer solar cells
摘要： A novel distorted lactam motif, namely 4,40-dialkyl-[6,60-bithieno[3,2-b]pyridine]-5,50(4H,40H)-dione (BTP), could lock itself by intramolecular hydrogen bonds. In view of the potential of the motif, two D–A conjugated polymers, PBDT-BTP-HD and PBDT-BTP-OD, with two different long side chains consisting of 4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b0]dithiophene (BDT) as a donor unit and BTP as an acceptor unit were designed and synthesized. Furthermore, the photophysical, electrochemical and photovoltaic properties of both polymers were investigated. The morphologies and molecular ordering of the neat polymers and blend films were also probed to relate the side chain structures with aggregation states and device parameters. The device based on PBDT-BTP-OD with IT-M exhibited a power conversion efficiency of up to 9.54% thanks to the synergistic effect of the building blocks and side-chain engineering. As a result, it is successfully demonstrated that the novel distorted lactam BTP is a promising building block in organic solar cells.
关键词： side-chain engineering,intramolecular hydrogen bonds,electron donor,distorted lactam,polymer solar cells
更新于2025-09-11 14:15:04
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Effect of electron donor and acceptor in dithienopyrrolobenzothiadiazole-based organic dyes for efficient quasi-solid-state dye-sensitized solar cells
摘要： Three new organic dyes H1-3 with dithienopyrrolobenzothiadiazole moiety as the π-bridge have been synthesized and applied in quasi-solid-state dye-sensitized solar cells. The influences of different electron acceptor of the sensitizers on the photo-physical, electrochemical and photovoltaic performances have been studied. The results show that the inserted electron-withdrawing unit benzothiadiazole in the acceptor part can obviously enhance the light-harvesting ability of the dyes. In addition, the introduced benzothiadiazole moiety in acceptor can increase the π-electron distribution in LUMO level, which may facilitate to the photogenergated electrons injection into TiO2 film. The effects of different electron donor on the solar cell performances have been evaluated. The dihexyloxy substituted triphenylamine is better to suppress the intermolecular aggregation and restrain electron recombination. Finally, the quasi-solid-state solar cell sensitized by dye H2 with 1 mM chenodeoxycholic acid as the co-adsorbent obtains a power conversion efficiency of 7.56%, which close to the level of dye N719 (7.66%) under the same condition.
关键词： Benzothiadiazole,Electron donor,Quasi-solid-state dye-sensitized solar cells,Power conversion efficiency,Dithienopyrrolobenzothiadiazole
更新于2025-09-11 14:15:04
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Structure-property relationship of novel monosubstituted Ru (II) complexes for high photocurrent and high efficiency DSSCs: Influence of donor versus acceptor ancillary ligand on DSSCs performance
摘要： Two novel high molar extinction coefficient monosubstituted-bipy Ru (II) complexes, IA-5 and IA-6, based on D-D-π and π-A-π-A ancillary ligands were synthesized with the aid of Knoevenagel reaction, to study the influence of the electron donor and electron acceptor ancillary ligand and number of anchoring group (COOH) on the light harvesting efficiency (LHE), ground and excited state oxidation potentials, incident-photon-to-current conversion efficiency (IPCE), short-circuit photocurrent density (J), and total solar-to-electric conversion efficiency (%η) for DSSCs, and their device performances were studied and showed a maximum of PCE of 7.81% (JSC = 17.61 mA cm?2, VOC = 0.69 V and FF = 64.05%) for dye IA-6 compared to PCE of 7.74% (JSC = 15.83 mA cm?2, VOC = 0.74 V and FF = 65.37%) for N719 dye. The photophysical and photoelectrochemical properties discussed herein addressed the significant impact of the electron donor and electron acceptor ancillary ligand and the number of anchoring groups on JSC and %η in DSSCs. The molecular structures of IA-5 and IA-6 were characterized using UV–Vis, emission spectrophotometry, FT-IR, ESI-MS, and 1H NMR. To probe the interrelationship between the chemical structure, photophysical and photoelectrochemical properties, molecular modeling studies, implemented in Gaussian, were employed. DFT/TD-DFT calculations were used to calculate the thermodynamics and electronic properties of IA-5 and IA-6 including HOMO and LUMO isosurfaces, lowest singlet-singlet electronic transitions (E0-0), ground and excited states oxidation potentials, GSOP and ESOP, which were in excellent agreement with the experimental results. Surprisingly, the insertion of the strong electron acceptor benzodithiazole in the ancillary ligand of IA-5 showed that the frontier LUMO shifted by 100% from 2,2′-bipyridyl-4,4′-dicarboxlic acid to the ancillary ligand containing benzodithiazole with electron injection accomplished from the anchoring group tethered to benzodithiazole. This new finding of relocating the LUMO from bipy-dicarboxylic acid to the other ancillary ligand would open the door for the molecular engineering of better light harvesting and more efficient Ru (II) complexes for DSSCs.
关键词： DFT and TD-DFT,Electron acceptor,Dye solar cells,Molecular modeling,Electron donor,Solar-to-electric conversion
更新于2025-09-10 09:29:36
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Photocatalytic reduction of uranyl: Effects of organic ligands and UV light wavelengths
摘要： Although previous studies demonstrate the photochemical reduction of uranyl (UO2) in the presence of various organic compounds, the actual roles of organic molecules as ligands and electron donors during the photoreaction are poorly understood. In this study, photochemical reduction of uranyl is examined with respect to organic ligands as electron donors and complexing agents, the role of titanium oxide (TiO2) nanoparticles as a photocatalyst, and the influence of UV light irradiation with emission peaks in the UV-A, UV-B, and UV-C ranges. Organic compounds with different binding affinities to uranyl such as acetate, ethylenediaminetetracetate (EDTA), oxalate, and hydroquinone were selected. Uranyl solutions prepared with one organic compound in a 1:8 molar ratio were irradiated under anoxic and acidic conditions (O2 < 1 ppm, pH 2.5). Uranyl removal by UV irradiation was better than 70 percent in the presence of oxalate and acetate, followed by hydroquinone (≈ 45 %) and EDTA (≈ 10 %). Uranyl removal was nearly constant at the UV-A, UV-B, and UV-C regions in the presence of acetate and oxalate whereas greater removal was observed in the EDTA and hydroquinone solutions exposed to UV-C and UV-A, respectively. These results reveal that uranyl reduction is mediated primarily by TiO2 nanoparticles and is highly dependent on the electron-donor compound. Addition of acetate enhances the uranyl photoreaction in hydroquinone solution. Dissolved EDTA species act as good electron donors at limited EDTA concentrations (1:2 to 1:4 uranyl to EDTA ratios) but at higher concentrations (for example, 1:8), uranyl-EDTA complexes such as [(UO2)HEDTA] compete for the surface sites on the TiO2 nanoparticles, hindering the photoreduction of uranyl. X-ray photoelectron spectroscopy (XPS) of the dried TiO2 powder shows that more than 70 percent of uranium partitioned into the solid phase is present as reduced forms with oxidation states (V) and (IV). The U4f spectra of U partitioned to the solid phase from the photoreaction with acetate reveal the predominance of U(IV) over U(V), whereas U(V) is the dominant oxidation state as a result of the photoreduction with EDTA. Our results suggest that formation of uranium-ligand complexes plays a critical role in controlling the reactivity of uranyl species and the stability of reduced uranium species in the course of the photoreaction.
关键词： organic ligand,rutile,P25,UV wavelength,electron donor,photocatalytic reduction of uranyl,anatase
更新于2025-09-09 09:28:46