- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Tailoring and Modifying an Organic Electron Acceptor toward the Cathode Interlayer for Highly Efficient Organic Solar Cells
摘要： With the rapid advance of organic photovoltaic materials, the energy level structure, active layer morphology, and fabrication procedure of organic solar cells (OSCs) are changed significantly. Thus, the photoelectronic properties of many traditional electrode interlayers have become unsuitable for modifying new active layers; this limits the further enhancement in OSC efficiencies. Herein, a new design strategy of tailoring the end-capping unit, ITIC, to develop a cathode interlayer (CIL) material for achieving high power conversion efficiency (PCE) in OSCs is demonstrated. The excellent electron accepting capacity, suitable energy level, and good film-forming ability endow the S-3 molecule with an outstanding electron extraction property. A device with S-3 shows a PCE of 16.6%, which is among the top values in the field of OSCs. More importantly, it is demonstrated that the electrostatic potential difference between the CIL molecule and the polymer donor plays a crucial role in promoting exciton dissociation at the CIL/active layer interface, contributing to additional charge generation; this is crucial for enhancement of the current density. The results of this work not only develop a new design strategy for high-performance CIL, but also demonstrate a reliable approach of density functional theory (DFT) calculation to predict the effect of the CIL chemical structure on exciton dissociation in OSCs.
关键词： organic electron acceptors,cathode interlayers,charge density difference,organic solar cells,high efficiency
更新于2025-09-12 10:27:22
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High Efficiency Perovskite Solar Cells: Materials and Devices Engineering
摘要： Since the first report on 9.7% efficient solid-state perovskite solar cell (PSC) in 2012, perovskite photovoltaics received tremendous attentions. Efforts to increase power conversion efficiency (PCE) have been continuously made. As a result, a record PCE of 25.2% was certified in 2019, which surpassed those achieved from the conventional solar cells based on CIGS and CdTe. The superb photovoltaic performance of PSC is related to the defect-tolerant property, the long carrier lifetime, the long diffusion length of photo-generated carriers, and the high absorption coefficient. In this review, materials and devices engineering are described for achieving stability and higher PCE in PSCs. From the practical point of view, key technologies for materials, coating, and device fabrication are described, which is expected to be helpful to achieve high efficiency PSCs. Moreover, interfacial engineering methodologies toward hysteresis-less and stable PSCs are also presented to give insight into better understanding ion migration and recombination in PSCs.
关键词： Solid-state,Perovskite solar cell,High efficiency,Hysteresis-less,Interfacial engineering,Stability,Coating
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - High-Efficiency, All-Dielectric Metasurfaces Down to the Deep Ultraviolet
摘要： In recent years, researchers have demonstrated various types of high-performance, all-dielectric metasurfaces operating in the infrared (IR) and visible regimes, paving the way towards high-efficiency, multi-functional and compact photonic systems. However, there has been a conspicuous lack of research on metasurfaces designed for operation in the ultraviolet (UV) region, which is the spectral region hosting various important applications such as photolithography, spectroscopy, astronomy, medical therapy, and high-resolution imaging. Unfortunately, direct scaling of the operation frequencies of metasurfaces based on the IR and visible designs down to the UV is challenging, due to the prohibitively high optical loss of typically employed constituent materials (e.g., Si, TiO2, GaN). Here, we report on low-loss, all-dielectric metasurfaces operating at UV wavelengths down to the deep-ultraviolet range. The metasurface are based on Hafnium Oxide (HfO2), an amorphous dielectric material most commonly exploited as a high static dielectric constant (high-k) material in integrated circuit fabrication, that is characterized by a wide-bandgap (5.8 eV). We develop a unique Damascene fabrication process, involving both low-temperature atomic layer deposition (ALD) of HfO2 onto patterned resist and back etching with Argon ion milling, to achieve high-aspect-ratio HfO2 nanostructures with straight and smooth sidewall profiles (Fig. 1a). We demonstrate a variety of polarization-independent UV metasurface devices having distinct functionalities, namely diffraction-limited focusing lenses (metalenses), hologram projectors (metaholograms) and self-accelerating beam generators, operating at two near-UV wavelengths (364 and 325 nm) with efficiencies as high as 75%. As an example, the measured intensity distribution for a NA=0.6 metalens operating at 325 nm reveals lensing with a circularly symmetric focal spot (Fig. 1b), of first-dark-ring diameter close to the theoretical diffraction-limited value. Scaling down metasurface critical dimensions, we achieve metaholograms (Fig. 1c) operating with high efficiencies at a record-short, deep-UV wavelength of 266 nm. The captured image for such a metahologram operating at 266 nm (Fig. 1d) demonstrates holographic projection with a measured efficiency of 60%. Finally, we demonstrate 266-nm, spin-multiplexed metasholograms of greater degree of geometric complexities, with efficiencies up to 61%. Our work paves the way towards compact and multifunctional UV flat optical systems.
关键词： deep ultraviolet,UV wavelengths,high-efficiency,all-dielectric metasurfaces,photonic systems
更新于2025-09-12 10:27:22
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10.3: <i>Invited Paper:</i> A Novel QD‐OLED Structure of High Optical Efficiency
摘要： QD-OLED device performance is unsatisfactory nowadays, due to the limited efficiency of blue OLED material as well as the low efficient converting rate of QD material. Here we proposed a novel structure of QD-OLED, using white OLED as the excitation. The device shows higher optical efficiency compared with QD-OLED with Blue OLED as excitation. In addition, a 6.6 inch green QD-OLED was demostrated with the proposed structure.
关键词： High efficiency,Excitation spectrum,QD-OLED,Quantum dot
更新于2025-09-11 14:15:04
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45.4: High Performance of Deep Blue OLEDs with Thermally Activated Sensitized Fluorescence Technology
摘要： The low efficiency of blue devices has been a bottleneck problem for OLED panel manufacturers for a long time. In this paper, we present the development of TASF materials technology for deep blue OLEDs with high Blue Index (current efficiency/CIE-y) around 300 at CIE-y=0.078 obtained at 1000 cd/m2.
关键词： TADF,TASF,high-efficiency,Thermally Activated Delayed Fluorescence,Thermally Activated Sensitized Fluorescence,deep blue,OLED
更新于2025-09-11 14:15:04
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45.3: TADF Emitters for Deep‐Blue OLEDs
摘要： Blue fluorescent OLEDs are still the bottleneck for the power consumption in today′s OLED panels. In recent years, the TADF technology has shown fast progress towards high- efficiency deep-blue emitter systems. The TADF technology can be used in a self-emitting or in a co-emitting (or hyper) approach. To make the co-emitting system work efficiently, the combination of TADF and fluorescent emitter has to be chosen carefully. In this paper, we will discuss how to match TADF and fluorescent emitter combinations for the co-emitting approach. We will also show results for highly efficient deep-blue hyper- fluorescent devices.
关键词： high efficiency,TADF,blue emitter,hyper-fluorescence,OLED
更新于2025-09-11 14:15:04
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Highly Foldable and Efficient Paper-Based Perovskite Solar Cells
摘要： Foldable paper-based solar cells are attractive power sources for wearable and portable applications. Currently, low power conversion efficiency (PCE) and degradation under different folding conditions restrict practical applications of paper-based solar cells. Herein are constructed solar cells on cellophane paper using oxide/ultrathin Ag/oxide (OMO) and perovskite as electrodes and absorbers, respectively. The perovskite solar cell (PSC) on cellophane exhibits a PCE of 13.19%, the highest among all the paper-based solar cells. More importantly, beneficial from ultrathin cellophane substrates combined with foldable OMO electrodes, PSCs on paper exhibit 50 single folding and 10 dual folding stability: they preserve 85.3 and 84.1% of the initial PCE after (cid:1)180(cid:3) and t180(cid:3) single folding for 50 cycles, respectively; and they remain 67.2 and 55.3% of the initial PCE after 10 inner and outer dual folding cycles, respectively. Furthermore, the solar cells after dual folding show serious cracks and delamination, leading to faster degradation than single folding. The highly efficient, foldable, and lightweight PSCs on cellophane are promising for future self-powered paper-based electronic applications.
关键词： foldable,perovskite solar cells,cellophane paper substrates,high-efficiency
更新于2025-09-11 14:15:04
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[IEEE 2018 IEEE International Conference on Consumer Electronics - Asia (ICCE-Asia) - Jeju (2018.6.24-2018.6.26)] 2018 IEEE International Conference on Consumer Electronics - Asia (ICCE-Asia) - Wideband Aperture-Coupled Stack-Patch Antenna Design with Characteristic Mode Analysis
摘要： These days’ RF communication frequencies, and technology is advancing towards a higher frequency spectrum with wide bandwidth for higher data rate, miniaturization and portability. For high frequency and wide bandwidth a low loss, efficient and compact wideband microstrip antenna development with convenient analysis is crucial. In this paper, we developed a wide band highly efficient stack patch antenna for Ku-band and analyze the model with characteristics mode analysis. The developed antenna has -10dB impedance bandwidth from 13.1-15.2GHz and -30dB bandwidth from 14-14.5GHz. Higher impedance matching leads to higher efficiency and high gain for the target center frequency of 14.25GHz.
关键词： characteristic mode analysis,high efficiency antenna,Stack patch antenna,wide bandwidth,low loss antenna
更新于2025-09-11 14:15:04
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High-efficiency organic solar cells with low voltage-loss of 0.46 V
摘要： The recent evolution of active components yielded brilliant progresses for organic solar cells (OSCs), yet the mechanism is needed to be clearly understood. In this work, two electron acceptors, a linear SN6-2Br and a V-shaped BTP-2Br, are developed with nitrogen atoms introduced to replace the traditional sp3-hybridized carbon in the fused ring. BTP-2Br possesses an electron-deficient central core, which exhibits slightly blue-shifted absorption as well as deepened HOMO-level compared with SN6-2Br. The corresponding photovoltaic performance from V-shaped BTP-2Br based devices exhibit superior performance especially in short-circuit current (Jsc), despite an enhanced absorption and charge carrier mobilities for SN6-2Br. The primary reason for the higher Jsc from BTP-2Br is faster exciton diffusion and dissociation in blends, than those of SN6-2Br. As a result, PBDB-TF:BTP-2Br based devices achieve a power conversion efficiency (PCE) of 13.84% with an voltage-loss of only 0.46 V, which is one of the lowest values ever reported. Moreover, we fabricated semitransparent OSCs that exhibit an excellent PCE of 9.62% with average visible transparency of 20.1%.
关键词： Organic solar cells,High efficiency,Semitransparent OSCs,Electron-deficient central core,Low voltage-loss
更新于2025-09-11 14:15:04
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Control and Optimization of Residential Photovoltaic Power Generation System With High Efficiency Isolated Bidirectional DC–DC Converter
摘要： Currently, residential photovoltaic power generation system is increasingly used worldwide. In this paper, an optimized structure of residential photovoltaic (PV) power generation system with 1500V DC bus is proposed. It includes PV panels, a three-level boost converter, a high efficiency isolated bidirectional DC-DC converter, battery and three-phase five-level DC-AC converter that can work under islanding mode or grid-connected mode. The higher DC bus voltage greatly reduces line loss and improves efficiency of the system. An energy management scheme used for the system is proposed in this paper to guarantee the stability of the system and to increase its economic benefits. Besides, the optimized method for the structure of the bidirectional dc-dc converter is proposed. This structure can achieve higher DC voltage gain and higher efficiency. Furthermore, for low voltage battery application in the residential system, LLC and CLLC under DC transformer (DCX) mode are evaluated and the LLC is selected as the isolated bidirectional DC-DC converter. The optimized designed method of bidirectional LLC is proposed. Finally, experiments are carried out to verify the performance of the optimized converters and the system.
关键词： high efficiency,Energy management scheme,isolated bidirectional DC-DC converter,residential photovoltaic power generation system,LLC converter
更新于2025-09-11 14:15:04