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- 实验方案
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Aloe vera-peel derived porous carbon integrated Co/Mn-oxide based nano-hybrids: An efficient electrocatalyst in advanced photovoltaics
摘要： We propose a facile strategy to synthesize highly electrocatalytic active nanohybrids by the integration of aloe vera-peel derived porous carbon into manganese-based and cobalt/manganese-based oxides. These nanohybrids exhibit unique three-dimensional porous network structures and possess high surface areas, providing numerous catalytic sites and multiple rapid electron transfer channels. In this work, the as-synthesized nanohybrids are used as accelerants for tri-iodide reduction in dye-sensitized solar cells, resulting in attractive cell efficiency and superior electrochemical stability. The solar cell with low-cost bio-based carbon integrated cobalt/manganese-oxide counter electrode exhibits higher photovoltaic efficiency than that of platinum electrode (7.01% vs. 6.44%). In addition, hybrid catalyst loaded counter electrodes also demonstrate long-term electrochemical stability in I3?/I? electrolyte, retaining 97% of its initial efficiency (6.83%/7.01%) in working cell, after going through multiple cyclic voltammetry scans. The utilization of synergistic effects of high performance constituents and controlled morphology is a key strategy to intensify the catalytic activity, electrochemical stability, and power conversion efficiency in advanced photovoltaics.
关键词： Dye-sensitized solar cell,Bio-based porous carbon,Cobalt manganese oxide,Morphology transformation,Electrocatalytic accelerants
更新于2025-09-16 10:30:52
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Pyrene-based hyperbranched porous polymers with doped Ir(piq)2(acac) red emitter for highly efficient white polymer light-emitting diodes
摘要： Here, we designed and prepared a series of hyperbranched porous polymers constructed using fluorene branches and pyrene core, and all hyperbranched porous polymers exhibit intense blue fluorescence, good morphological stability, and high thermal stability. Further, it is found that the aperture sizes for hyperbranched porous polymers can be adjusted by simply changing the content of pyrene and fluorene in the synthesis process. When the feed ratios of pyrene in the total polymers is 15 mol%, the optimized aperture size was obtained, which is slightly larger than the maxlength of complementary red emitter Bis(1-phenylisoquinoline)(acetylacetonate) iridium (III) (Ir(piq)2acac), indicating the Ir(piq)2acac can well distributed in the apertures of hyperbranched porous polymers in co-doped film of Ir(piq)2acac and hyperbranched porous polymers. The fabricated polymer-light-emitting diode (PLED) with such co-doped film as light-emitting layer realizes good white emission with almost equal blue and red emission intensity from hyperbranched porous polymers and Ir(piq)2acac. The balanced electroluminescent (EL) spectra contribute to ideal Commission Internationale de l’Eclairage (CIE) coordinate of (0.326, 0.374) located at white light zone. In addition, the device also achieves high device performance with maximum luminance and current efficiency reaching 5369 cd/m2 and 8.35 cd/A, respectively. We believe that such porous-structure polymers have huge potential applications in the development of highly efficient white PLEDs with reducing production cost.
关键词： White light,Electroluminescence spectra,Polymer light-emitting diodes,Hyperbranched porous polymers
更新于2025-09-16 10:30:52
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Performance of thin silicon solar cells with a quasi-monocrystalline porous silicon layer on the rear side
摘要： The present study employs porous silicon (PS) or quasi-monocrystalline porous silicon (QMPS) as a reflector material on the rear side. It presents an analytical model that simulates the performance of n+–p–p+ thin silicon solar cell with a QMPS layer on the rear side. The development of the model involves the formulation of a complete set of equations for the photo-current density that is then solved analytically in the base region, including the photocurrent generated under the effect of the light reflected by QMPS layer. This also takes the contribution of the back p+-region (back surface field) to the generated photocurrent into consideration. The enhancements brought by the thin film QMPS with regard to photovoltaic (PV) parameters are then investigated and compared to those brought by the conventional silicon solar cell. Moreover, the effect of the QMPS layer on the current–voltage characteristics J–V and the internal quantum efficiency (IQE) of thin silicon solar cells are simulated by means of AFORS-HET software. These simulations show that the improvement of the PV parameters is due to an increase in the transport parameters of minority carriers in the p-region.
关键词： porous silicon,thin silicon solar cells,quasi-monocrystalline porous silicon,photovoltaic parameters,AFORS-HET software
更新于2025-09-12 10:27:22
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Flexible and Degradable Multimodal Sensor Fabricated by Transferring Laser-Induced Porous Carbon on Starch Film
摘要： Flexible sensors (FSs) hold great potential in wearable and intelligent equipment, but the preparation of degradable and multimodal FSs is urgently demanded, which may simplify the sensor matrix and reduce electronic waste. Here in this work, a multimodal and degradable FS was fabricated by transferring laser-induced porous carbon onto starch film. The obtained sensor showed three modes that can detect strain (with gauge factor (GF) = 134.2, response time of 130 ms, and stability >1000 times), temperature (25?90 °C), and pressure (0?250 kPa). The sensor can be used for monitoring human motions, detection of spatial pressure, and multiple stimuli. More importantly, the sensor was demonstrated to be degradable in water, suggesting it is a "green" electronic device being free of electronic pollution. This kind of multimodal and degradable FS may find wide applications in health and sports monitoring, flexible electronics, artificial intelligence, and so on.
关键词： Starch,Degradable,Multimodal,Porous carbon,Flexible sensor
更新于2025-09-12 10:27:22
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Reagentless fabrication of a porous graphene-like electrochemical device from phenolic paper using laser-scribing
摘要： This study fabricated a portable, high-performance, and reagentless electrochemical devices using CO2 laser-scribing process, which allowed localized carbonization of a non-conductive and low-cost polymer platform, i.e., phenolic-paper. The carbonized material was extensively characterized by Raman spectroscopy, XPS, XRD, SEM, and electrochemical impedance spectroscopy. The carbon-based electrodes were obtained from the photothermal process induced by CO2 laser radiation and subsequently subjected to electrochemical treatment to fabricate a functional material with excellent conductivity and low charge-transfer resistance. Additionally, the laser-scribed electrodes presented a porous structure with graphene-like domains, thus indicating both potential for on-site electroanalytical applications and better performance than conventional carbon electrodes.
关键词： Graphene domains,Electrochemical sensors,Disposable devices,Porous material,Laser pyrolysis
更新于2025-09-12 10:27:22
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Study of bone regeneration and osseointegration effect of a novel selective laser melted titanium-tantalum-niobium-zirconium alloy scaffold
摘要： Titanium-tantalum-niobium-zirconium (Ti-Ta-Nb-Zr) alloy is a novel material currently available for orthopedic applications. However, these scaffolds, manufactured using traditional methods, present disadvantages such as irregular pore size, unsuitable mechanical features, and poor connectivity between pores. In this study, porous Ti-Ta-Nb-Zr (Ti 60%, Ta 2%, Nb 36%, Zr 2%) scaffolds were printed by selective laser melting (SLM) with controllable pore size of 300~400 μm. The mechanical properties of the SLM-manufactured scaffolds were evaluated, as well as its osteogenesis in vitro and osteointegration in vivo. Porous Ti-Ta-Nb-Zr scaffolds yielded superior cell-proliferation and cell-adhesion results with human bone mesenchymal stem cells (hBMSCs) compared with porous Ti6Al4V scaffolds. The osteogenic differentiation experiment demonstrated enhanced osteogenic differentiation of hBMSCs in the Ti-Ta-Nb-Zr group than in Ti6Al4V group. After the porous Ti-Ta-Nb-Zr or control scaffolds were implanted into a cylindric bone defect in the rabbit lateral femoral condyle, the initial radiological results confirmed the excellent osteogenic activity of the novel 3D-printed scaffolds. Histological analysis further indicated that the Ti-Ta-Nb-Zr scaffolds promoted bone regeneration and osteointegration more effectively than Ti6Al4V scaffolds did. Our findings demonstrate that the SLM-manufactured porous Ti-Ta-Nb-Zr scaffold has considerable potential for clinical orthopedic application.
关键词： porous Ti-Ta-Nb-Zr,selective laser melting,osteointegration,orthopedic implant,osteogenesis
更新于2025-09-12 10:27:22
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Numerical study of the geometrically graded metal foam for concentrated photovoltaic solar cell cooling
摘要： Concentrated photovoltaic cell (CPV) had gained much attention recently due to high efficiency at a competitive cost. However, efficiency of CPV is inversely proportional to the temperature. Hence, it is important to reduce the maximum temperature and variation of temperature across the CPV. Metal foam with its high specific surface area, thermal conductivity and tortuous flow path to promote mixing is an ideal candidate for thermal management for CPV. However, the thermal performance of the metal foam may drop from upstream to downstream and lead to poor cooling performance near the outlet. In this study, functionally graded metal foam is attached on the CPV to extract the heat generated. Functionally graded aluminum foam with gradual variation porosity are modelled to investigate the thermal performance and flow field using computational thermal fluid dynamics analysis. Heat transfer correlation, permeability and resistance loss coefficient are extracted from the literature and used in the simulation. The results showed that functionally graded metal foam with gradual reducing porosity offered a better temperature uniformity for the CPV. Therefore, this approach will further extend the cycle life as well as improve the overall efficiency of the CPV.
关键词： solar cell,cooling,metal foam,CFD,porous media
更新于2025-09-12 10:27:22
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Current Controlled Switching in Si/PS/a-Si Heterostructure
摘要： Current controlled switching has been observed in p-type crystalline Silicon (p-c-Si)/porous Si (PS)/n-type hydrogenated amorphous Silicon (n-a-Si:H) heterostructure. Mechanism of the switching is proposed consideringpresence of trapped carriers at the silicon nanocrystal-SiOx interface. A part of the trapped charges are considered to be bound near the n-a-Si:H/PS and PS/p-c-Si interface forming an additional coulomb barrier for the majority carriers. It is assumed that during the flow of current through the PS layer, the captured carriers get de-trapped by impact-excitation leading to breaking of the barrier after certain threshold value resulting in the switching. This model matches well with the experimental results.
关键词： amorphous silicon,interface,porous silicon,Switching
更新于2025-09-12 10:27:22
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Computer and Experimental Modelling of Heat Leakage from Porous Substrates of LED Lighting Devices
摘要： In this paper we propose a mathematical and physical model of a porous substrate, evaluate influence of the pores size and quantity on the substrate’s specific surface and present experimental results of the heat leakage kinetics by the porous substrate. Performances of the porous aluminium oxide printed circuit board with the record heat conductivity of 120 W/mK are presented.
关键词： porous substrate,printed board,physical model,heat conductivity,LED lighting device
更新于2025-09-12 10:27:22
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Porous single-wall carbon nanotube templates decorated with all-inorganic perovskite nanocrystals for ultra-flexible photodetectors
摘要： As an inevitable optoelectronic material with unique properties, halide perovskites attracted increasing attention in recent years. Meanwhile, hybridization of nanostructured perovskites with one-dimensional (1D) or two-dimensional (2D) functional materials has exhibited unique applications in nanotechnology. In this communication, a highly conducting porous single-wall carbon nanotube (p-SWCNT) template decorated with phase-pure CsPbBr3 nanocrystals by simple solution-phase technique was demonstrated, and the ultra-flexible photodetector Au/p-SWCNT:CsPbBr3/Au showed high sensitivity even in highly bending state. Also, the mechanism of wetting CsPbBr3 along p-SWCNT and the detailed fabrication process for ultra-flexible photodetectors were highlighted. The direct contact (in-situ) on p-SWCNT by crystallization of perovskite precursor can enhance the charge transfer at their interface effectively. At applied bias of +5 V, the optimized photodetector Au/p-SWCNT:CsPbBr3/Au exhibits a maximum photoresponsivity of 41.0 AW-1 with a specific detectivity of 1.67×1012 Jones under an incident 232 μW/cm2 520 nm illumination. In addition, it exhibits excellent mechanical and electrical properties even under high strain (i.e. bending angle up to -17°) and recovers the original performance after repeated bending cycles upto 1000 times. Our experimental results showed that such a hybrid materials provide a promising method for rigid and flexible optoelectronic devices.
关键词： Porous single-wall carbon nanotube (p-SWCN),inorganic perovskite nanocrystals,flexible photodetector,CsPbBr3,visible light photodetector
更新于2025-09-12 10:27:22