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- 摘要
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- 实验方案
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[IEEE 2019 IEEE Sustainable Power and Energy Conference (iSPEC) - Beijing, China (2019.11.21-2019.11.23)] 2019 IEEE Sustainable Power and Energy Conference (iSPEC) - Detection of High-Impedance Line-Line Fault in Photovoltaic Arrays Based on Voltage Divider
摘要： The recently proposed dual mode logic (DML) gates family enables a very high level of energy-delay optimization flexibility at the gate level. In this paper, this flexibility is utilized to improve energy efficiency and performance of combinatorial circuits by manipulating their critical and noncritical paths. An approach that locates the design’s critical paths and operates these paths in the boosted performance mode is proposed. The noncritical paths are operated in the low energy DML mode, which does not affect the performance of the design, but allows significant energy consumption reduction. The proposed approach is analyzed on a 128 bit carry skip adder. Simulations, carried out in a standard 40 nm digital CMOS process with VDD = 400 mV, show that the proposed approach allows performance improvement of X2 along with reduction of energy consumption of X2.5, as compared with a standard CMOS implementation. At VDD = 1.1 V, improvements of 1.3X and 1.5X in performance and energy are achieved, respectively.
关键词： energy efficiency,Dual Mode Logic,critical paths,energy-delay optimization,high performance
更新于2025-09-23 15:19:57
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Selfa??Additive Lowa??Dimensional Ruddlesdena??Popper Perovskite by the Incorporation of Glycine Hydrochloride for Higha??Performance and Stable Solar Cells
摘要： The recent rise of low-dimensional Ruddlesden–Popper (RP) perovskites is notable for superior humidity stability, however they suffer from low power conversion efficiency (PCE). Suitable organic spacer cations with special properties display a critical effect on the performance and stability of perovskite solar cells (PSCs). Herein, a new strategy of designing self-additive low-dimensional RP perovskites is first proposed by employing a glycine salt (Gly+) with outstanding additive effect to improve the photovoltaic performance. Due to the strong interaction between CO and Pb2+, the Gly+ can become a nucleation center and be beneficial to uniform and fast growth of the Gly-based RP perovskites with larger grain sizes, leading to reduced grain boundary and increased carrier transport. As a result, the Gly-based self-additive low-dimensional RP perovskites exhibit remarkable photoelectric properties, yielding the highest PCE of 18.06% for Gly (n = 8) devices and 15.61% for Gly (n = 4) devices with negligible hysteresis. Furthermore, the Gly-based devices without encapsulation show excellent long-term stability against humidity, heat, and UV light in comparison to BA-based low-dimensional PSCs. This approach provides a feasible design strategy of new-type low-dimensional RP perovskites to obtain highly efficient and stable devices for next-generation photovoltaic applications.
关键词： low-dimensional perovskites,high-performance solar cells,self-additive effect,stable solar cells,glycine hydrochloride
更新于2025-09-23 15:19:57
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A prenucleation strategy for ambient fabrication of perovskite solar cells with high device performance uniformity
摘要： Humidity is known to be inimical to the halide perovskites and thus typically avoided during fabrication. The poor fundamental understanding of chemical interactions between water and the precursors hampers the further development of perovskite fabrication in ambient atmosphere. Here, we disclose a key finding that the ambient water could promote the formation of lead complexes, which when uncontrolled would make their way into large intermediate fibrillar crystallites and thus discontinuous perovskite films unfavorable for photovoltaics among others. To counter this effect, a prenucleation strategy is proposed, which embodies the controlled burst of profuse intermediate nuclei. Consequently, we are able to obtain a compact and uniform perovskite layer, which affords high efficiency perovskite solar cells. More excitingly, the solar cells show high performance uniformity, demonstrating the distinctive advantages of our prenucleation strategy. This work sheds light on developing reliable and cost-effective fabrication methods for industrial production of perovskite solar cells.
关键词： perovskite solar cells,ambient fabrication,water interaction,high performance uniformity,prenucleation strategy
更新于2025-09-23 15:19:57
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High-performance white organic light-emitting diodes with doping-free device architecture based on the exciton adjusting interfacial exciplex
摘要： White organic light-emitting diodes (WOLEDs) with doping-free device architecture have aroused more attention due to their attractive merits such as simplified fabrication procedures and reduced costs. However, the electroluminescence performance of that is still manifestly unsatisfactory and needs to be further improved. Here, high-performance doping-free two-color and three-color WOLEDs with the accurate manipulation of excitons have been successfully fabricated by optimizing the interfacial exciplex. As a result, two-color WOLEDs exhibit the controllable electroluminescence spectra with a wide correlated color temperature (CCT) spanning from 2878 to 9895 K at the voltage of 4 V, as well as the maximum forward-viewing power and current efficiencies of 83.2 lm W?1 and 63.3 cd A?1, respectively. The three-color WOLED not only realizes the maximum efficiencies of 50.1 lm W?1 and 44.7 cd A?1, but also exhibits superior color stability with a color rendering index of 86, a CCT of 2679 K, and a Commission International de I’Eclairage coordinates of (0.49, 0.46) at the voltage of 5 V. Such surprising efficiencies obtained in our WOLEDs indicate that the reasonable application of interfacial exciplex should be a helpful way to develop high-performance and low cost WOLEDs with a simple technology.
关键词： high-performance,color stability,White organic light-emitting diodes,doping-free,interfacial exciplex
更新于2025-09-23 15:19:57
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High-Performance Ternary Organic Solar Cells with Controllable Morphology via Sequential Layer-by-Layer Deposition
摘要： Ternary blending of light harvesting materials has been proven to be a potential strategy to improve the efficiency of solution processed organic solar cells (OSCs). However, the optimization of ternary system is usually more complicated than the binary one as the morphology of conventional ternary blend films is very difficult to control, thus undermining the potential of ternary OSCs. Herein, we report a general strategy for better control of the morphology of ternary blend films composed of a polymer donor and two non-fullerene small molecule acceptors for high-performance OSCs using sequential layer-by-layer (LbL) deposition method. The resulted LbL films form bicontinuous interpenetrating network structure with high crystallinity of both the donor and acceptor materials, showing efficient charge generation, transport and collection properties. In addition, the power conversion efficiencies (PCEs) of the ternary LbL OSCs are less sensitive to the blending ratio of the third component acceptor, providing more room to optimize the device performance. As a result, optimal PCEs of over 11%, 13 % and 16 % were achieved for the LbL OSCs composed of PffBT4T-2OD/IEICO-4F:FBR, PBDB-T-SF/IT-4F:FBR and PM6/Y6:FBR, respectively. Our work provides useful and general guidelines for the development of more efficient ternary OSCs with better controlled morphology.
关键词： sequential layer-by-layer deposition,non-fullerene acceptor,ternary organic solar cell,high performance,morphology control
更新于2025-09-23 15:19:57
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Narrow bandgap difluorobenzochalcogenadiazole-based polymers for high-performance organic thin-film transistors and polymer solar cells
摘要： A bithiophene donor unit, 3-alkoxy-3’-alkyl-bithiophene (TRTOR), was copolymerized with difluorobenzochalcogenadiazole (ffBZ) containing different heteroatoms on their diazole structure to afford a series of PffBZ copolymers (where Z = X, T, Se) with narrow optical bandgaps in the range of 1.34-1.47 eV. The effects of ffBZ heteroatoms (O, S, and Se) on the optical properties, electrochemical characteristics and film morphologies of polymers as well as device performance were fully investigated. The results revealed that the highest occupied molecular orbitals (HOMOs) of polymers are gradually elevated accompanied by increased material solubility in common organic solvents as the size of heteroatoms increases. The PffBZ copolymers exhibit substantial hole mobility of 0.08-1.6 cm2 V-1 s-1 in organic thin-film transistors (OTFTs). The PffBX, PffBT, and PffBSe-based polymers exhibit maximum power conversion efficiencies (PCEs) of 5.47%, 10.12%, and 3.65%, respectively in polymer solar cells (PSCs). For PffBZ copolymers, the alkyl chain exerts a great influence on the morphology of the polymer:PC71BM blend films and hence affect PCEs in PSCs. It was found that the performing of polymers branching on the 2nd position for alkyl chain and the 3rd position for alkoxy chain were the best among PffBT and PffBSe-based polymers, and it is different from the tetrathiophene-based benchmark polymer branching on the 2nd position of the alkyl chain. X-ray diffraction revealed that all PffBZ-based polymers has obvious a face-on dominated orientation, and that chalcogen atom and branched position on alkoxy chain have a great influence on the morphologies of neat and blend films. The above results indicated that the branching positions and chalcogen atoms should be carefully optimized to maximize performance.
关键词： polymer solar cells,high-performance,difluorobenzochalcogenadiazole,organic thin-film transistors,narrow bandgap
更新于2025-09-23 15:19:57
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Cost effective synthesis of p-type Zn-doped MgAgSb by planetary ball-milling with enhanced thermoelectric properties
摘要： A melamine-based porous organic polymer (mPMF) was synthesized as solid phase extraction (SPE) adsorbent for inline SPE-high performance liquid chromatography (HPLC)-ultraviolet detector (UV) analysis of five phytohormones. Melamine contributed to the rich π-electron and N-containing triazine structure for mPMF, which could form π-π interaction and intermolecular hydrogen bond with -COOH containing phytohormones. The synthesized mPMF adsorbent shows extremely high extraction efficiency for five target analytes (>80%) including salicylic acid, indole-3-acetic acid, abscisic acid, 2,4-dichlorophenoxyacetic acid and 1-naphthalene acetic acid. The factors affecting extraction of the target phytohormones were investigated and the optimized experimental conditions were established. The linear range was 0.2–100 μg/L for five target phytohormones. The developed method of mPMF-inline-SPE-HPLC-UV was applied for the analysis of trace target phytohormones in tomato and grape juice samples, and the recovery in the range of 83.1–116% and 87.2–121% was obtained for the spiked tomato and grape juice, respectively. This method has the advantages of high sensitivity and good reproducibility, and it has good application potential for the analysis of phytohormones in fruit samples. Moreover, inline analysis avoided the problems of sample pollution and sample loss, and provided a sample throughput of 5/h.
关键词： Phytohormones,Porous organic polymer,Fruit juice,Inline solid phase extraction,High performance liquid chromatography
更新于2025-09-19 17:15:36
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Scalable Hardware-Based On-Board Processing for Run-Time Adaptive Lossless Hyperspectral Compression
摘要： Hyperspectral data processing is a computationally intensive task that is usually performed in high-performance computing clusters. However, in remote sensing scenarios, where communications are expensive, a compression stage is required at the edge of data acquisition before transmitting information to ground stations for further processing. Moreover, hyperspectral image compressors need to meet minimum performance and energy-efficiency levels to cope with the real-time requirements imposed by the sensors and the available power budget. Hence, they are usually implemented as dedicated hardware accelerators in expensive space-grade electronic devices. In recent years though, these devices have started to coexist with low-cost commercial alternatives in which unconventional techniques, such as run-time hardware reconfiguration are evaluated within research-oriented space missions (e.g., CubeSats). In this paper, a run-time reconfigurable implementation of a low-complexity lossless hyperspectral compressor (i.e., CCSDS 123) on a commercial off-the-shelf device is presented. The proposed approach leverages an FPGA-based on-board processing architecture with a data-parallel execution model to transparently manage a configurable number of resource-efficient hardware cores, dynamically adapting both throughput and energy efficiency. The experimental results show that this solution is competitive when compared with the current state-of-the-art hyperspectral compressors and that the impact of the parallelization scheme on the compression rate is acceptable when considering the improvements in terms of performance and energy consumption. Moreover, scalability tests prove that run-time adaptation of the compression throughput and energy efficiency can be achieved by modifying the number of hardware accelerators, a feature that can be useful in space scenarios, where requirements change over time (e.g., communication bandwidth or power budget).
关键词： dynamic and partial reconfiguration,FPGAs,Data compression,high-performance embedded computing,on-board processing,hyperspectral images
更新于2025-09-19 17:15:36
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Metal-Semiconductor-Metal ?μ-Ga2O3 Solar-Blind Photodetectors with a Record High Responsivity Rejection Ratio and Their Gain Mechanism
摘要： In recent years, Ga2O3 solar-blind photodetector (SBPD) has been attached great attention for its potential application in solar-blind imaging, deep space exploration, and confidential space communication, etc. In this work, we demonstrated an ultrahigh performance ε-Ga2O3 metal-semiconductor-metal (MSM) SBPD. The fabricated photodetectors exhibited record-high responsivity and fast decay time of 230 A/W and 24 ms, respectively, compared with MSM-structured Ga2O3 photodetectors reported to date. Additionally, the ε-Ga2O3 MSM SBPD presents ultrahigh detectivity of 1.2×1015 Jones with low dark current of 23.5 pA under the operation voltage of 6 V, suggesting its strong capability of detecting an ultraweak signal. The high sensitivity and wavelength selectivity of the photodetector were further confirmed by the record high responsivity rejection ratio (R250nm/R400nm) of 1.2×105. From the temperature-dependent electrical characteristics in the dark, the thermionic field emission and Poole-Frenkel emission were found to be responsible for the current transport in the low and high electric field regimes, respectively. In addition, the gain mechanism was revealed by the Schottky barrier lowering effect due to the defect states at the interface of metal contact and Ga2O3 or in the bulk of Ga2O3 based on current transport mechanism and density functional theory (DFT) calculation. These results facilitate a better understanding of ε-Ga2O3 photoelectronic devices and provide possible guidance for promoting their performance in future solar-blind detection applications.
关键词： rejection ratio,metal-organic chemical vapor deposition,ε-Ga2O3,responsivity,high-performance,solar-blind photodetector
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Highly Accelerated Thermal Cycling Test for New Type of Crystalline Silicon Photovoltaic Modules
摘要： We present the main results of the performance test campaign of the Mid-Infrared European Extremely Large Telescope Imager and Spectrograph (METIS) Cold Chopper Demonstrator (MCCD). This tip/tilt mirror, which operates at a temperature of 77 K, is one of the critical components in the METIS for the European Extremely Large Telescope. The performance requirements of the MCCD relate to the field of fast and very accurate reference tracking. We discuss the applicability of different high-performance motion control strategies and describe the control synthesis of a repetitive and of a novel hybrid controller. We identified the presence of nonlinearities in the plant, which limits the performance of the hybrid controller. The repetitive controller shows very promising results and can handle the nonlinearities in the system. This experimental phase concludes the MCCD program, which was initiated to verify the feasibility of a high-performance cryogenic tip/tilt mirror at an early stage in the METIS development. Because of the very promising test results, no significant changes to the hardware will be implemented. We believe that minor adjustments will suffice to meet all requirements of the final hardware after integration with the METIS instrument.
关键词： motion control,repetitive control,hysteresis,hybrid control,control synthesis,high-performance,tip/tilt mechanism
更新于2025-09-19 17:13:59