- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Thioalkyl-Functionalized Bithiophene (SBT)-Based Organic Sensitizers for High-Performance Dye-Sensitized Solar Cells
摘要： A series of 3,3′-dithioalkyl-2,2′-bithiophene (SBT)-based organic chromophores were designed and developed for the use in dye-sensitized solar cells (DSSCs). By appropriate structural modification of the SBT π-linkers with different alkyl chains and conjugated thiophene units, chromophore aggregation and interfacial charge recombination could be suppressed to a remarkable degree. Single-crystal and optical/electrochemical data clearly show that the SBT core is nearly planar with the torsional angle <1°, likely via S(alkyl)···S(thiophene) intramolecular locks. Therefore, this highly π-conjugated unit should enhance panchromatic light-harvesting and prove to be an excellent core for organic dye. For comparison, the 3,3′-dialkyl-2,2′-bithiophene (BT)-based dye was also prepared. Under 1 sun (100 mW cm?2) illumination, an optimized SBT-6 dye-sensitized cell indicates a short-circuit current density (JSC) of 17.21 mA cm?2, an open-circuit voltage (VOC) of 0.78 V, and a fill factor (FF) of 0.71, corresponding to a power conversion efficiency (η) of 9.47%, which is nearly two times higher than that of alkylated bithiophene (BT)-based chromophores. Finally, the proposed sensitizer SBT-6 exhibited an excellent η of 23.57% under the T5 fluorescent illumination of 6000 lux. To the best of our knowledge, this is the highest power conversion efficiencies (PCE) value reported to date among the studied thiophene or bithiophene-based chromophores.
关键词： aggregation,T5 fluorescent illumination,panchromatic light-harvesting,3, 3′-dithioalkyl-2, 2′-bithiophene,S(alkyl)···S(thiophene) intramolecular locks
更新于2025-09-23 15:19:57
-
Dual-band light-emitting diode based on microwheel cavity
摘要： Compact and broadband electroluminescent (EL) devices have garnered considerable interest in recent years. In this study, we have fabricated a light-emitting diode (LED) based on a GaN microwheel cavity with a peak emission wavelength of 438 nm. Another emission peak at 512 nm is realized by coating CH3NH3PbBr3 on the LED. The microwheel-cavity–based LED is fabricated by photolithography and inductively coupled plasma etching process. The opto-electrical performance of the device is characterized in terms of the EL spectrum, luminescence intensity, full width at half maximum, and 3 dB bandwidth. Compared to the device without the CH3NH3PbBr3 layer, the proposed device exhibits dual-band illumination and higher 3 dB bandwidth with potential applications in optical communication.
关键词： CH3NH3PbBr3,dual-band illumination,GaN,microwheel cavity,light-emitting diode
更新于2025-09-23 15:19:57
-
High responsivity ZnO based p-n homojunction UV-photodetector with series Schottky Barrier
摘要： In the present article, we proposed a p-n homojunction photodetector with a series Schottky barrier and a high value of responsivity in the ultraviolet region. The thin-film photodetector makes use of a junction between an RF-sputtered n-type ZnO nanostructure and a p-type CZO thin film derived through the spin coating process on an ITO coated glass substrate. Palladium metal contacts have been deposited to form the Schottky barrier in series with p-n homojunction. The device has been simulated, fabricated, and tested only after ensuring the stability of the p-type CZO thin film. The measured I-V characteristics of fabricated photodetector under illuminated and dark conditions showed excellent UV response and good rectification property. The device exhibits a peak responsivity of 13.2 A/W for a reverse biasing voltage of 3 V. This value is much above the values reported by others for ZnO based photodetector.
关键词： CZO,photodiode,U-V illumination,ZnO,Schottky junction
更新于2025-09-23 15:19:57
-
Photochemical dynamics under incoherent illumination: Light harvesting in self-assembled molecular J-aggregates
摘要： Transport phenomena in organic, self-assembled molecular J-aggregates have long attracted a great deal of attention due to their potential role in designing novel organic photovoltaic devices. A large number of theoretical and experimental studies have been carried out describing excitonic energy transfer in J-aggregates under the assumption that excitons are induced by a coherent laser-light source or initialized by a localized excitation on a particular chromophore. However, these assumptions may not provide an accurate description to assess the efficiency of J-aggregates, particularly as building blocks of organic solar cells. Under natural conditions, J-aggregates would be subjected to an incoherent source of light (as is sunlight), which would illuminate the whole photosynthetic complex rather than a single molecule. In this work, we present the first study of the efficiency of photosynthetic energy transport in self-assembled molecular aggregates under incoherent sunlight illumination. By making use of a minimalistic model of a cyanine dye J-aggregate, we demonstrate that long-range transport efficiency is enhanced when exciting the aggregate with incoherent light. Our results thus support the conclusion that J-aggregates are, indeed, excellent candidates for devices where efficient long-range incoherently induced exciton transport is desired, such as in highly efficient organic solar cells.
关键词： incoherent illumination,exciton transport,organic solar cells,J-aggregates,photosynthetic energy transport
更新于2025-09-23 15:19:57
-
Sensitive and Rapid Cancer Diagnosis with Immunoplasmonic Assay Based on Plasmonic Nanoparticles: Toward Fine-Needle Aspiration Cytology
摘要： Fine-needle aspiration cytology is a minimally invasive diagnostic strategy. However, collected specimens have to undergo a series of complex preparation steps, thus limiting the use of fine-needle aspiration cytology as a diagnostic approach for cytopathologists. In this study, we propose a cytology approach, easily adaptable to conventional one, by employing plasmonic biomarkers (gold(red_scattering), silver/gold(blue_scattering), and silver/gold(green_scattering) nanoparticles), each having a well-defined optical feature. Plasmonic nanoparticles, incubated with the suspension cells, are fully visible and differentiable on the cell membranes under the darkfield lateral RGB (Red-Green-Blue) side-illumination microscopy. The post-fabrication of plasmonic nanoparticles by the conjugation of a specific antibody (anti-human epidermal growth factor receptor 2: HER2) directly allows to visualize the selectively recognized antigens of the suspension cells (MDA-MB-453++HER2 and Jurkat-HER2) in co-cultures and individual cultures by using the side-illumination compared to the conventional dark-field visualization protocol. We also incubate two cancer cell lines (trypsinized MDA-MB-231++CD44 and MDA-MB-453++HER2) with anti-CD44 and anti-HER2 functionalized plasmonic nanoparticles, and nano-immunoplasmonic and immunofluorescence assays show a good agreement with each other for the recognition of expressed antigens (CD44 and HER2). Our results demonstrate a remarkable potential of plasmonic nanoparticles for a simple and rapid examination of small population of cells from collected specimens by using nano-immunoplasmonic approach and the side-illumination microscopy.
关键词： Fine-needle aspiration cytology,Plasmonic nanoparticles,Plasmonic biomarkers,Cancer diagnosis,Immunoplasmonic Assay,Side-illumination microscopy
更新于2025-09-23 15:19:57
-
Conversionless efficient and broadband laser light diffusers for high brightness illumination applications
摘要： Laser diodes are efficient light sources. However, state-of-the-art laser diode-based lighting systems rely on light-converting inorganic phosphor materials, which strongly limit the efficiency and lifetime, as well as achievable light output due to energy losses, saturation, thermal degradation, and low irradiance levels. Here, we demonstrate a macroscopically expanded, three-dimensional diffuser composed of interconnected hollow hexagonal boron nitride microtubes with nanoscopic wall-thickness, acting as an artificial solid fog, capable of withstanding ~10 times the irradiance level of remote phosphors. In contrast to phosphors, no light conversion is required as the diffuser relies solely on strong broadband (full visible range) lossless multiple light scattering events, enabled by a highly porous (>99.99%) non-absorbing nanoarchitecture, resulting in efficiencies of ~98%. This can unleash the potential of lasers for high-brightness lighting applications, such as automotive headlights, projection technology or lighting for large spaces.
关键词： high-brightness illumination,solid-state lighting,light diffusers,laser diodes,hexagonal boron nitride
更新于2025-09-23 15:19:57
-
Light-Induced Sulfur Transport inside Single-Walled Carbon Nanotubes
摘要： Filling of single-walled carbon nanotubes (SWCNTs) and extraction of the encapsulated species from their cavities are perspective treatments for tuning the functional properties of SWCNT-based materials. Here, we have investigated sulfur-modified SWCNTs synthesized by the ampoule method. The morphology and chemical states of carbon and sulfur were analyzed by transmission electron microscopy, Raman scattering, thermogravimetric analysis, X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopies. Successful encapsulation of sulfur inside SWCNTs cavities was demonstrated. The peculiarities of interactions of SWCNTs with encapsulated and external sulfur species were analyzed in details. In particular, the donor–acceptor interaction between encapsulated sulfur and host SWCNT is experimentally demonstrated. The sulfur-filled SWCNTs were continuously irradiated in situ with polychromatic photon beam of high intensity. Comparison of X-ray spectra of the samples before and after the treatment revealed sulfur transport from the interior to the surface of SWCNTs bundles, in particular extraction of sulfur from the SWCNT cavity. These results show that the moderate heating of filled nanotubes could be used to de-encapsulate the guest species tuning the local composition, and hence, the functional properties of SWCNT-based materials.
关键词： X-Ray spectroscopy,encapsulation,illumination,single-walled carbon nanotubes,sulfur,de-encapsulation
更新于2025-09-23 15:19:57
-
Azimuthal illumination enabled ultra-high polar angle sensitivity by Bloch surface wave resonance refractive index sensor
摘要： The scheme of polar angle space refractive index (RI) sensor based on grating coupled Bloch surface wave (BSW) resonance excited by azimuthal illuminations is studied. It is shown that, for any polar angle, one can always find a case of BSW resonance with the tangential wave vector of the BSW mode perpendicular to that of the incident electromagnetic wave. When the sensor is designed to work around this resonance, ultra-high polar angle sensitivity can be expected. The numerical simulated polar angle sensitivity reaches as large as 1786 degree per RI unit (Deg/RIU), which is almost one order higher than that can be found in literatures.
关键词： Bloch surface wave,azimuthal illumination,polar angle sensitivity,refractive index sensor
更新于2025-09-23 15:19:57
-
Selective UV Absorbance of Copper Chalcogenide Nanoparticles for Enhanced Illumination Durability in Perovskite Photovoltaics
摘要： The inherent optical and electrical properties of inorganic nanoparticles (NPs) give them high potential applicability in advanced energy devices. In this study, PEDOT:PSS was remodeled with aqueous synthesized copper-based chalcogenide NPs, and the novel properties were demonstrated. Raman spectra were used to analyze the changes in intrinsic binding of PEDOT:PSS and derive the main peak shift. X-ray diffraction spectral analysis showed that a photoactive layer stably formed on PEDOT:PSS with or without NPs. Perovskite photovoltaics (PPV) were fabricated with the remodeled PEDOT:PSS as the hole transport layer, and the electrical properties were evaluated. The charge factor and power conversion efficiency were higher in the NP-based PPVs than in the reference PEDOT:PSS devices. The charge behavior in the NP-based PPVs was investigated, and the following were identified: (1) improved device drive characteristics with photocurrent vs internal voltage, (2) tenfold increase in the hole mobility of the hole-only devices, (3) optimized efficiency in the photo-generated exciton dissociation test, and (4) improved charge transport resistance based on the impedance spectrum. The inherent optical properties of the NPs were examined in an illumination-durability test of the perovskite material without encapsulation. Under continuous light exposure, PPV in NP-based devices showed better electrical stability than in the reference devices. Field-effect scanning electron microscopy analysis indicated that perovskite particles in the NP-based samples have advanced morphological stability compared to the reference samples. Thus, integrating NPs is an efficient strategy for fabricating advanced PPVs with improved device efficiency and illumination-durability, in a more cost-effective and eco-friendly manner.
关键词： illumination durability,PEDOT:PSS modification/reforming effect,charge transport,copper-based chalcogenide NPs,perovskite photovoltaics
更新于2025-09-23 15:19:57
-
Impact of Illumination Correlated Color Temperature, Background Lightness, and Painting Color Content on Color Appearance and Appreciation of Paintings
摘要： Lighting design for art exhibitions has a significant impact on the enjoyment and understanding of the displayed artworks. In particular, the selection of the light sources and the design of the museum space affect the visitors’ visual perceptions of the artworks and their color appearance. This project investigated some of the potential factors—the correlated color temperature (CCT) of the illumination, the overall color content of the painting and the lightness of its background—affecting a painting’s color appearance and appreciation in a museum setting. The study involved a survey conducted in the laboratory with both na?ve observers and lighting experts. The CCT of the lighting was found to be the main factor affecting the painting’s appearance and the observers’ overall preference for the lighting arrangements, whereas the overall hue content of the painting and the background lightness had a minor influence. Furthermore, it has been found that the perceived brightness increases along with the CCT.
关键词： paintings,Artworks illumination,CCT,visual perception,visual appreciation,color vision,museum lighting,background lightness,color appearance
更新于2025-09-19 17:15:36