- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Indolo[3,2- <i>b</i> ]indole donor-based D–π–A dyes for DSCs: investigating the role of π-spacers towards recombination
摘要： Dye solar cells (DSCs) are gaining increasing interest since the recent realization of their high-performance in low/indoor light environments. Fused conjugated metal-free organic dyes have become a prominent class of dyes used in DSC in recent times by virtue of their better backbone rigidity, efficient charge transport properties, and the opportunity they provide for further structural modifications. Herein, we report the synthesis and characterization of three metal-free D–π–A organic dyes employing indolo[3,2-b]indole as the donor unit. The optical, electrochemical and photovoltaic properties have been analyzed in detail as a function of π-spacers, namely, benzene (IID-1), thiophene (IID-2) and furan (IID-3). Eventually, the best performance was demonstrated by the dye bearing benzene as the π-spacer. The role of recombination in determining the photovoltaic performance as a function of the nature of π-spacers was explored in detail, using various perturbation techniques on the fabricated devices, and compared with the results obtained from molecular orbital calculations.
关键词： π-spacers,Recombination,2-b]indole,Dye solar cells,Indolo[3,Photovoltaic performance,D–π–A dyes
更新于2025-09-19 17:15:36
-
Naphthalene and perylene diimides – better alternatives to fullerenes for organic electronics?
摘要： The LUMO levels of rylene diimides are highly comparable to those of fullerenes but this class of molecules offers tunability of both HOMO and LUMO levels and the related band gap by either simple substitution at the aromatic core or annulation to give expanded p-scaffolds. In this article we highlight the most outstanding achievements during the last decade in terms of charge carrier mobility for organic thin-film and single crystal field-effect transistors as well as photovoltaic performance for both small molecule and polymeric compounds.
关键词： fullerenes,perylene diimides,organic electronics,photovoltaic performance,naphthalene diimides,charge carrier mobility
更新于2025-09-19 17:15:36
-
Significant influence of the benzothiophene ring substitution position on the photovoltaic performance of benzodithiophene-based donor polymers
摘要： In order to investigate the e?ects of the substitution position on the photovoltaic performance of donor polymers, two benzothiophene ring substituted benzo(1,2-b:4,5-b0)dithiophene (BDT)-based conjugated polymers (PBDTBTs-BDD and PBDTTBs-BDD) are designed and synthesized. The variation in the substitution position has small influences on the photophysical properties but has a great e?ect on the intramolecular p–p stack structure, charge transport and photovoltaic properties. PBDTBTs-BDD (with the 6-position of the benzothiophene substituent) exhibited a smaller p–p stacking distance of 3.67 ? compared to 4.11 ? seen for PBDTTBs-BDD (with the 2-position of the benzothiophene substituent). And the charge mobilities of PBDTBTs-BDD-based devices are higher and more balanced than those of PBDTTBs-BDD-based devices, which are highly beneficial for reducing recombination of free carriers and then lead to a higher short-circuit current density (JSC) and fill factor (FF) of devices. With ITIC or Y6 as non-fullerene acceptors, PBDTBTs-BDD-based devices exhibit power conversion efficiencies (PCE) of 7.76% and 12.07%, respectively, which are higher than those of PBDTTBs-BDD-based devices (5.04% and 5.81%). This work demonstrates that the photovoltaic properties of donor polymers can be highly tunable through slight modifications of their side chain structures.
关键词： benzothiophene,donor polymers,photovoltaic performance,power conversion efficiencies,non-fullerene acceptors
更新于2025-09-19 17:13:59
-
Conjugated Organic Cations Enable Efficient Self-Healing FASnI3 Solar Cells
摘要： The introduction of large-volume amines (LVAs) in Sn-based perovskite films has been shown to lead to promising power conversion efficiency (PCE) in Pb-free perovskite solar cells (PSCs). However, the LVAs adopted so far (e.g., phenylethylammonium [PEA] and butylammonium [BA]) are insulating and could impede charge extraction within the perovskite film. Herein, a conjugated LVA, 3-phenyl-2-propen-1-amine (PPA), is introduced in formamidinium tin iodide (FASnI3) perovskite. Our results show that the incorporation of PPA results in enlarged grain sizes, reduced trap density, preferential orientation, efficient charge extraction, and enhanced structural stability of FASnI3 film. These positive effects help in achieving efficient PSCs with a PCE as high as 9.61% with negligible hysteresis and outstanding stability (remains 92% of its initial PCE value after 1,440 h). Furthermore, the presence of PPA enables a self-healing action of PSCs. Most importantly, we report large-area (1 × 1 cm2) Sn-based PSCs achieving PCE of 7.08%.
关键词： FASnI3 solar cells,Lead-free perovskite,Photovoltaic performance,Self-healing,Conjugated organic cations
更新于2025-09-19 17:13:59
-
High performance and stable nonfullerene acceptor-based organic solar cells for indoor to outdoor light
摘要： We synthesized a donor polymer of bis(2-ethylhexyl)thiophene-substituted benzodithiophene (BDT-Th) and 1,3-bis(2-ethylhexyl)-5,7-di(thiophene-2-yl)benzo[1,2-c:4,5-c′]dithiophene-4,8-dione, for which the BDT-Th unit includes chlorine and sulfur-bridged 2-ethylhexyl in the thiophene side group. When compared with PBDB-TF, which includes fluorine and 2-ethylhexyl in BDT-Th, PBDB-TSCl shows more efficient exciton dissociation and charge-generation, which is probably because large dipole moment changes from ground to excited states lead to reduced exciton binding energy. Consequently, despite small donor-acceptor interface in the bulk-heterojunction (BHJ) film, PBDB-TSCl achieves higher photovoltaic performance than PBDB-TF under various light intensities; PBDB-TSCl achieved higher efficiency of 13.13% than 12.12% of PBDB-TF under 1 sun illumination. Moreover, PBDB-TSCl showed the highest efficiency of 21.53% with fill factor (FF) of 76.29% under a 500 lux fluorescence lamp, whereas PBDB-TF has lower efficiency of 15.57% with FF of 65.25%. Furthermore, the PBDB-TSCl device shows improved thermal stability due to more stabilized morphology of its BHJ film.
关键词： indoor light,nonfullerene acceptor,outdoor light,organic solar cells,thermal stability,photovoltaic performance
更新于2025-09-19 17:13:59
-
Effect of fluoro-substituted acceptor-based ancillary ligands on the photocurrent and photovoltage in dye-sensitized solar cells
摘要： Herein, we report four novel heteroleptic ruthenium (II) complexes, namely SD-7 to SD-10, containing fluoro- and trifluoro- methyl antennas as substituents on the ancillary ligands for dye-sensitized solar cells, and were compared to the benchmark dye N719. Photosensitizers (dyes) SD-7 to SD-10 were synthesized according to a typical one-pot three-step procedure with the corresponding ancillary ligands (LS-7 to LS-10). All the dyes were characterized by ATR-FTIR, 1H NMR and mass spectrometry. Furthermore, the photophysical, electrochemical and photovoltaic performances were compared with N719. The band gaps, ground and excited state oxidation potentials were measured. The photovoltaic performance of the dyes showed that SD-7 with five fluorine atoms and SD-8 with eCF3 at the –ortho position of the phenyl moiety outperformed the benchmark dye N719 with the efficiencies of 8.03% and 8.17%, respectively, with current density of 19.57 and 19.46 mA?cm?2, respectively, and open-circuit voltages of 0.65 V and 0.69 V, respectively, under optimized conditions. The fabricated solar devices at lab-scale showed a systematic trend of decreasing JSC when the fluoro-substituted dyes were sensitized on TiO2: SD-7 (with five –F) > SD-8 (with one eCF3 at ortho position) > SD-9 (with one eCF3 at para position) > SD-10 (with two eCF3, one at ortho and one at para position). This can be attributed to the greater number of fluorine atoms directly attached to sp2 hybridized carbon atoms, which greatly enhanced the dipole moment and intimate electronic coupling of SD-7 with TiO2 nanoparticles leading to better photocurrent density.
关键词： Fluoro-based dyes,Acceptor-based ancillary ligand,Photovoltaic performance,Dye-sensitized solar cells,Ruthenium complex
更新于2025-09-19 17:13:59
-
Heterogeneous Cationa??Lattice Interaction and Dynamics in Triple-Cation Perovskites Revealed by Infrared Vibrational Nanoscopy
摘要： Hybrid organic-inorganic perovskites exhibit extraordinary photovoltaic performance. This is believed to arise from almost liquid-like low-energy interactions among lattice ions and charge carriers. While spatial variations have recently been identified over multiple length scales in the optoelectronic responses, the relationship of the heterogeneity and the soft cation-lattice interactions has remained elusive. Here, we apply multivariate infrared vibrational nano-imaging to a formamidinium (FA)-methylammonium (MA)-cesium triple cation perovskite. By using the FA vibrational resonance as a probe of its local chemical environment, through spatial variation and correlation in composition, strength of cation-lattice coupling and its associated few-ps vibrational dynamics, we reveal how a varying local reaction field is correlated with the cation-lattice coupling. We attribute the associated heterogeneous lattice contraction to a non-uniform distribution of cesium cations. The observed varying elasticity of the lattice leads to disordered charge-phonon coupling and polaron formation, the control of which is central to improving perovskite photovoltaics.
关键词： charge-phonon coupling,infrared vibrational nano-imaging,Hybrid organic-inorganic perovskites,lattice contraction,photovoltaic performance,cation-lattice coupling,polaron formation,vibrational dynamics
更新于2025-09-19 17:13:59
-
An Ultravioleta??Deposited MoO <sub/>3</sub> Film as Anode Interlayer for Higha??Performance Polymer Solar Cells
摘要： An ultraviolet-deposited MoO3 film is developed as anode interlayer based on molybdenum(V) chloride as precursor. The ultraviolet-deposited MoO3 film is prepared from the precursor film (spin coated from its solution) with ultraviolet irradiation treatment, and the preparation process of the MoO3 film is facile, low cost, and compatible with mass production and flexible substrate. The composition of the MoO3 film is analyzed by X-ray photoelectron spectroscopy. The work function as well as the surface morphology and wettability of indium tin oxide (ITO) modified by the MoO3 film are investigated by ultraviolet photoelectron spectroscopy, atomic force microscopy, and contact angle tester, respectively, where the analyses show the ITO modified by the MoO3 anode interlayer can offer excellent energy level alignment and interface contact with active layer. The photovoltaic performance of nonfullerene polymer solar cells (PSCs) based on the MoO3 anode interlayer is researched with typical and relatively low-cost PBDB-T:ITIC as active layer, and the ITO/MoO3-based device shows the highest power conversion efficiency of 9.27% compared with the bare ITO-based device (3.69%) and the ITO/PEDOT:PSS-based device (9.15%). The results demonstrate the great potential of the ultraviolet-deposited MoO3 film as anode interlayer for high-performance PSCs.
关键词： ultraviolet irradiation,photovoltaic performance,MoO3 film,polymer solar cells,anode interlayer
更新于2025-09-19 17:13:59
-
Surface Ligands for Methylammonium Lead Iodide Films: Surface Coverage, Energetics, and Photovoltaic Performance
摘要： Surface ligand treatment provides a promising approach to passivate defect states, improve material and device stability, manipulate interfacial energetics, and increase the performance of perovskite solar cells (PSCs). To facilitate targeted selection and design of surface ligands for PSCs, it is necessary to establish relationships between ligand structure and perovskite surface properties. Herein, surface ligands with different binding groups are investigated to determine their extent of surface coverage, whether they form a surface monolayer or penetrate the perovskite, how they influence material energetics and photoluminescence, and how this combination of factors affects PSC performance. Ultraviolet and inverse photoelectron spectroscopy measurements show that surface ligands can significantly shift the ionization energy and electron affinity. These changes in surface energetics substantially impact PSC performance, with the performance decreasing for ligands that create less favorable energy landscapes for electron transfer from MAPbI3 to the electron transport layer, C60.
关键词： defect passivation,perovskite solar cells,interfacial energetics,surface ligands,photovoltaic performance
更新于2025-09-19 17:13:59
-
Phenothiazine dyes containing a 4-phenyl-2-(thiophen-2-yl) thiazole bridge for dye-sensitized solar cells
摘要： Two novel phenothiazine dyes bearing a single or double cyanoacrylic acid acceptors, which share the same electron donor phenothiazine and the same 4-phenyl-2-(thiophen-2-yl)thiazole p-bridge, were synthesized. Thus, phenothiazine dyes with D-p-A and A-D-p-A framework were con?gured, and their photophysical properties and photovoltaic performance were investigated. The incorporation of another cyanoacrylic acid acceptor was found to bene?t the loading amount on TiO2, the light-harvesting ability, and the electron-injection ef?ciency. Dye with double cyanoacrylic acid acceptors showed a double short-circuit current compared with dye with a single acceptor. Therefore, dye with double cyanoacrylic acid acceptors achieved improved photoelectric conversion ef?ciency 4.35% (JSC ? 10.29 mA cm?2, VOC ? 0.65 V, FF ? 0.65) under standard global AM 1.5 G solar condition with dye N719 (7.19%) as a reference.
关键词： Phenothiazine,Photovoltaic performance,4-Phenyl-2-(thiophen-2-yl)thiazole,Double acceptors,Dye-sensitized solar cell
更新于2025-09-19 17:13:59