- 标题
- 摘要
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- 实验方案
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A portable non-enzyme photoelectrochemical ascorbic acid sensor based on BiVO4 electrode under 20?W LED light
摘要： BiOI film was electrodeposited deposited on fluorine doped tin oxide (FTO), then it was transformed into a nanoporous BiVO4 film by annealing at 420 ?C. The BiVO4/FTO electrode is used as photoelectrochemical (PEC) sensor to detect ascorbic acid (AA) for the first time. Under illumination of low power 20 W LED lamp, the current density of the sensor increases with the increase of AA concentration. The proposed PEC sensor exhibited a sensitive detection for AA in a wide range from 5 μM to 300 μM with a low detection limit of 1 μM (S/N=3) and sensitivity of 293 μA mM-1 cm-2. A portable AA detection device was constructed with a 20W LED lamp as the light source, BiVO4/FTO electrode as an anode, Pt as a cathode, and ammeter as a photoelectric signal receiver. The concentration of AA detected by this device is close to that measured by the electrochemical workstation (RSD<10%), which makes the sensor practical and portable.
关键词： Nanoporous BiVO4,Ascorbic acid,Portable device,Photoelectrochemical sensor
更新于2025-09-19 17:13:59
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Superior photoresponse MIS Schottky barrier diodes with nanoporous:Sna??WO <sub/>3</sub> films for ultraviolet photodetector application
摘要： Highly ordered nanoporous structure based MIS type photo-detector is a promising device for next-generation optoelectronic applications due to their excellent light absorption, better mechanical strength, low density with larger diffusion coefficient and charge accommodation ability. Here, we fabricated a highly sensitive MIS Schottky barrier diodes by sandwiching nanoporous:Sn-WO3 films as interfacial layer prepared by jet nebulizer spray pyrolysis technique. XRD confirmed the polycrystalline nature with monoclinic and orthorhombic phase of Sn-WO3 films, whose crystallite size gradually increased with Sn concentration. FE-SEM of Sn-WO3 composite films with 12 wt% of Sn exhibited unique surface morphology of nanoplate, nanowire and nanoporous-like structure. Optical band gap energy improved from 3.2 to 3.6 eV with Sn concentration. Establishing the nanoporous structure of Sn-WO3, we are the first to report on the photo-diode properties of Cu/nanoporous:Sn-WO3/p-Si diodes which recorded a positive photo-response with higher reverse saturation current under illumination. It is supported through enhanced detectivity of the interface layer with increasing Sn concentration. We have achieved an ultra-high responsivity of 5083.5 mA/W for the diode fabricated with 12 wt% of Sn, which is 154 times higher than pure WO3. The presence of nanoporous:Sn-WO3 layer in MIS diode recorded ~60% quantum efficiency making it ideal for the ultra-violet photo-detector application.
关键词： MIS Schottky barrier diodes,Sn-WO3,photo-detector,nanoporous,ultra-violet
更新于2025-09-19 17:13:59
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Love Wave Surface Acoustic Wave Sensor with Laser-Deposited Nanoporous Gold Sensitive Layer
摘要： Laser-deposited gold immobilization layers with different porosities were incorporated into Love Wave Surface Acoustic Wave sensors (LW-SAWs). Acetylcholinesterase (AChE) enzyme was immobilized onto three gold interfaces with different morphologies, and the sensor response to chloroform was measured. The response of the sensors to various chloroform concentrations indicates that their sensing properties (sensitivity, limit of detection) are considerably improved when the gold layers are porous, in comparison to a conventional dense gold layer. The results obtained can be used to improve properties of SAW-based biosensors by controlling the nanostructure of the gold immobilization layer, in combination with other enzymes and proteins, since the design of the present sensor is the same as that for a Love Wave biosensor.
关键词： pulsed laser deposition,Au,gas sensor,Love Wave,nanoporous film,SAW sensor
更新于2025-09-19 17:13:59
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Hollow Porous Gold Nanoshells with Controlled Nanojunctions for Highly Tunable Plasmon Resonances and Intense Field Enhancements for Surface-Enhanced Raman Scattering
摘要： Plasmonic metal nanostructures with nanogaps have attracted great interest owing to their controllable optical properties and intense electromagnetic fields that can be useful for a variety of applications, but precise and reliable control of nanogaps in three-dimensional nanostructures remains a great challenge. Here, we report the control of nanojunctions of hollow porous gold nanoshell (HPAuNS) structures by a facile oxygen plasma-etching process and the influence of changes in nanocrevices of the interparticle junction on the optical and sensing characteristics of HPAuNSs. We demonstrate a high tunability of the localized surface plasmon resonance (LSPR) peaks and surface-enhanced Raman scattering (SERS) detection of rhodamine 6G (R6G) using HPAuNS structures with different nanojunctions by varying the degree of gold sintering. As the neck region of the nanojunction is further sintered, the main LSPR peak shifts from 785 to 1350 nm with broadening because the charge transfer plasmon mode becomes more dominant than the dipolar plasmon mode, resulting from the increase of conductance at the interparticle junctions. In addition, it is demonstrated that an increase in the sharpness of the nanojunction neck can enhance the SERS enhancement factor of the HPAuNS by up to 4.8-fold. This enhancement can be ascribed to the more intense local electromagnetic fields at the sharper nanocrevices of interparticle junctions. The delicate change of nanojunction structures in HPAuNSs can significantly affect their optical spectrum and electromagnetic field intensity, which are critical for their practical use in a SERS-based analytical sensor as well as multiple-wavelength compatible applications.
关键词： sintering,plasma etching,nanoporous gold,nanocrevice junction,surface-enhanced Raman scattering,plasmonic nanostructure
更新于2025-09-16 10:30:52
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Simple and Rapid Fabrication Process of Porous Silicon Surface Using Inductively Coupled Plasma Reactive Ion Etching
摘要： In this study, the simple and rapid formation of porous silicon on a pillar array structure using inductively coupled plasma reactive ion etching (ICP-RIE) is realized. This method can render the outermost surface porous without using an additional etching or deposition apparatus because the same equipment is used to form the structure. As a basic experiment, we attempted to etch the structure by considerably varying three parameters (bias power, chamber pressure, and gas ?ow rate) in ICP-RIE. The etching step condition was determined for the porous structure from the result. Furthermore, we obtained a porous pillar surface while almost maintaining the structure by performing multicycle etching and an additional passivation step. A number of pores (diameter: ～100 nm) were formed randomly on the side wall of the pillar array using the proposed method. Compared with original pillar, the surface roughness of porous pillar increased by 48%. [2019-0216]
关键词： nanoporous materials,Etching,microstructure,silicon
更新于2025-09-16 10:30:52
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Recycled Utilization of a Nanoporous Au Electrode for Reduced Fabrication Cost of Perovskite Solar Cells
摘要： Perovskite solar cells (PSCs) using metal electrodes have been regarded as promising candidates for next-generation photovoltaic devices because of their high efficiency, low fabrication temperature, and low cost potential. However, the complicated and rigorous thermal deposition process of metal contact electrodes remains a challenging issue for reducing the energy pay-back period in commercial PSCs, as the ubiquitous one-time use of a contact electrode wastes limited resources and pollutes the environment. Here, a nanoporous Au film electrode fabricated by a simple dry transfer process is introduced to replace the thermally evaporated Au electrode in PSCs. A high power conversion efficiency (PCE) of 19.0% is demonstrated in PSCs with the nanoporous Au film electrode. Moreover, the electrode is recycled more than 12 times to realize a further reduced fabrication cost of PSCs and noble metal materials consumption and to prevent environmental pollution. When the nanoporous Au electrode is applied to flexible PSCs, a PCE of 17.3% and superior bending durability of ≈98.5% after 1000 cycles of harsh bending tests are achieved. The nanoscale pores and the capability of the porous structure to impede crack generation and propagation enable the nanoporous Au electrode to be recycled and result in excellent bending durability.
关键词： reduce fabrication costs,nanoporous Au films,bending durability,perovskite solar cells,recycled utilization
更新于2025-09-16 10:30:52
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Finite element modeling of effective permittivity in nanoporous epoxy composite filled with hollow nanosilica
摘要： The relative permittivity of nanoporous epoxy composites (NPCs) filled with hollow nanosilica is lower than that of unfilled epoxy resin. The low permittivity is considered to arise from the existence of cavity volume, but the effects of nanosilica particle shape, particle size distribution and agglomeration are not clear. In this study, the relative permittivity of an NPC filled with hollow nanosilica is modeled by using finite-element method including the above-mentioned factors. The proposed model successfully reproduces the experimentally-obtained low permittivity of NPCs. The effect of cavities is significant, while particle corner shape, particle size distribution or particle agglomeration is not dominant.
关键词： epoxy,permittivity,nanoporous composite,hollow nanosilica
更新于2025-09-16 10:30:52
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Ionization-field instability in the laser-induced breakdown of nanoporous dielectric
摘要： The theory of ionization-?eld instability in a continuous homogeneous medium is generalized to the heterogeneous nanoporous one with the purpose to clear and analyze the mechanism of nanograting formation during the optical breakdown process in a transparent dielectric (fused silica) containing multiple small inclusions (nanobubbles) with a lowered ionization threshold. Based on the Maxwell Garnett approximation extended to include the size effect caused by the ?nite ratio of the bubble sizes to the scale of unstable perturbations, we have obtained the equation system describing the spatiotemporal evolution of the plasma density, average ?eld, and effective dielectric permittivity and have derived the characteristic equation connecting the temporal growth rate of these perturbations with their spatial period. Analysis of the roots of this equation shows that the unstable periodic perturbation structure having the maximal growth rate is close in character to the nanogratings observed experimentally (modulation in the direction of the pump wave polarization with the period approximately equal to the half-wavelength in the host material).
关键词： laser-induced breakdown,nanograting formation,nanoporous dielectric,Maxwell Garnett approximation,ionization-field instability
更新于2025-09-12 10:27:22
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3D nanoporous plasmonic chips for extremely sensitive NO <sub/>2</sub> detection
摘要： The detection of toxic gas molecules using the surface-enhanced Raman spectroscopy (SERS) technique is very challenging due to the low affinity of gas molecules. Here, we report extremely sensitive SERS-based NO2 gas sensors based on 3D nanoporous Au nanostructures with a high affinity for NO2 gas molecules and high density of hotspots.
关键词： SERS,toxic gas molecules,3D nanoporous plasmonic chips,surface-enhanced Raman spectroscopy,NO2 detection
更新于2025-09-12 10:27:22
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23.2: <i>Invited Paper:</i> All silicon passive addressed micro‐LED displays with nanoporous Si/ITO‐free nanomesh layers as light emitting pixels
摘要： In this paper, we will concentrate on the usage of novel technologies and nanostructured materials to fabricate low cost high efficient micro LED displays with unique features.
关键词： nanoporous silicon,nanomesh films,micro-LED,passive addressing
更新于2025-09-11 14:15:04