The Experts below are selected from a list of 36264 Experts worldwide ranked by ideXlab platform
Xiangfeng Duan - One of the best experts on this subject based on the ideXlab platform.
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Porous Silicon nanowires
Nanoscale, 2011Co-Authors: Xiangfeng DuanAbstract:In this mini-review, we summarize recent progress in the synthesis, properties and applications of a new type of one-dimensional nanostructures-single crystalline Porous Silicon nanowires. The growth of Porous Silicon nanowires starting from both p- and n-type Si wafers with a variety of dopant concentrations can be achieved through either one-step or two-step reactions. The mechanistic studies indicate the dopant concentration of Si wafers, oxidizer concentration, etching time and temperature can affect the morphology of the as-etched Silicon nanowires. The Porous Silicon nanowires are both optically and electronically active and have been explored for potential applications in diverse areas including photocatalysis, lithium ion batteries, gas sensors and drug delivery.
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Photocatalytic Properties of Porous Silicon Nanowires.
Journal of Materials Chemistry, 2010Co-Authors: Yongquan Qu, Xing Zhong, Yujing Li, Lei Liao, Yu Huang, Xiangfeng DuanAbstract:Porous Silicon nanowires are synthesized by metal assisted wet-chemical etching of highly-doped Silicon wafers. The resulting Porous Silicon nanowires exhibit a large surface area of 337 m2 g−1 and a wide spectrum absorption across the entire ultraviolet, visible and near infrared regime. We further demonstrate that platinum nanoparticles can be loaded onto the surface of the Porous Silicon nanowires with controlled density. These combined advancements make the Porous Silicon nanowires an interesting material for photocatalytic applications. We show that the Porous Silicon nanowires and platinum nanoparticle loaded Porous Silicon nanowires can be used as effective photocatalysts for photocatalytic degradation of organic dyes and toxic pollutants under visible irradiation, and thus are of significant interest for organic waste treatment and environmental remediation.
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Photocatalytic properties of Porous Silicon nanowires
Journal of Materials Chemistry, 2010Co-Authors: Xiangfeng DuanAbstract:Porous Silicon nanowires are synthesized through metal assisted wet-chemical etch of highly-doped Silicon wafer. The resulted Porous Silicon nanowires exhibit a large surface area of 337 m(2)·g(-1) and a wide spectrum absorption across the entire ultraviolet, visible and near infrared regime. We further demonstrate that platinum nanoparticles can be loaded onto the surface of the Porous Silicon nanowires with controlled density. These combined advancements make the Porous Silicon nanowires an interesting material for photocatalytic applications. We show that the Porous Silicon nanowires and platinum nanoparticle loaded Porous Silicon nanowires can be used as effective photocatalysts for photocatalytic degradation of organic dyes and toxic pollutants under visible irradiation, and thus are of significant interest for organic waste treatment and environmental remediation.
Claudia Pacholski - One of the best experts on this subject based on the ideXlab platform.
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photonic crystal sensors based on Porous Silicon
Sensors, 2013Co-Authors: Claudia PacholskiAbstract:Porous Silicon has been established as an excellent sensing platform for the optical detection of hazardous chemicals and biomolecular interactions such as DNA hybridization, antigen/antibody binding, and enzymatic reactions. Its Porous nature provides a high surface area within a small volume, which can be easily controlled by changing the pore sizes. As the porosity and consequently the refractive index of an etched Porous Silicon layer depends on the electrochemial etching conditions photonic crystals composed of multilayered Porous Silicon films with well-resolved and narrow optical reflectivity features can easily be obtained. The prominent optical response of the photonic crystal decreases the detection limit and therefore increases the sensitivity of Porous Silicon sensors in comparison to sensors utilizing Fabry-Perot based optical transduction. Development of Porous Silicon photonic crystal sensors which allow for the detection of analytes by the naked eye using a simple color change or the fabrication of stacked Porous Silicon photonic crystals showing two distinct optical features which can be utilized for the discrimination of analytes emphasize its high application potential.
Sharon M. Weiss - One of the best experts on this subject based on the ideXlab platform.
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Porous Silicon Optical Waveguides
Handbook of Porous Silicon, 2021Co-Authors: Sharon M. Weiss, Xing WeiAbstract:Porous Silicon optical waveguides have attracted attention for applications ranging from optoelectronics to chemical and biological sensors. This chapter describes various waveguide geometries that have been achieved in Porous Silicon, including single and multilayer architectures. Depending on the processing parameters, oxidized Porous Silicon waveguides can be fabricated with losses below 0.5 dB/cm. While these losses are a challenge for some optoelectronics applications, sensor applications of Porous Silicon waveguides have flourished. Recent innovations have led to demonstrations of the label-free detection of nucleic acid molecules, proteins, and toxins with sensitivities as low as 10−6/RIU.
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Imprinting Porous Silicon
Handbook of Porous Silicon, 2021Co-Authors: Judson D. Ryckman, Sharon M. WeissAbstract:This chapter describes the capabilities of the direct imprinting of Porous substrates (DIPS) technique for patterning and modifying the physical properties of Porous Silicon films. DIPS can achieve very high-resolution two-dimensional and three-dimensional patterning with feature sizes below 100 nm while eliminating the need for intermediate masking materials and etch recipes that complicate and increase the expense of other patterning techniques. The DIPS process utilizes a reusable master stamp to imprint the desired pattern into Porous Silicon by directly applying the stamp to the Porous substrate with a pressure on the order of 100 MPa. This process is performed in a matter of seconds at room temperature. In addition to enabling the fabrication of patterned Porous Silicon structures, DIPS also enables morphological control over material properties including porosity, pore size, and refractive index. Examples of designs fabricated by DIPS include grating-coupled wave guides, free-standing particles, and curvilinear structures such as lenses.
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Porous Silicon Optical Waveguides
2020Co-Authors: Sharon M. WeissAbstract:Porous Silicon optical waveguides have attracted attention for applications ranging from optoelectronics to chemical and biological sensors. This chapter describes various waveguide geometries that have been achieved in Porous Silicon, including single and multilayer architectures. Depending on the processing parameters, oxidized Porous Silicon waveguides can be fabricated with losses below 0.5 dB/cm. While these losses are a challenge for some optoelectronics applications, sensor applications of Porous Silicon waveguides have flourished. Recent innovations have led to demonstrations of the label-free detection of nucleic acid molecules, proteins, and toxins with sensitivities as low as 10 /RIU. S.M. Weiss (*) • X. Wei Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, USA e-mail: sharon.weiss@vanderbilt.edu # Springer International Publishing Switzerland 2014 L. Canham (ed.), Handbook of Porous Silicon, DOI 10.1007/978-3-319-05744-6_83 815
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Porous Silicon Waveguide Biosensors
2006 IEEE LEOS Annual Meeting Conference Proceedings, 2006Co-Authors: Sharon M. WeissAbstract:Porous Silicon waveguide biosensors are demonstrated as a new platform for high sensitivity, label-free sensing. Comparison to the performance of evanescent wave-based sensors and other Porous Silicon-based sensors will be explored.
S D Collins - One of the best experts on this subject based on the ideXlab platform.
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Porous Silicon formation mechanisms
Journal of Applied Physics, 1992Co-Authors: R L Smith, S D CollinsAbstract:Recent reports describing photoluminescence in Porous Silicon have heightened the level of interest in it as a unique electronic material, and have created a need for a more complete understanding of the mechanism of Porous Silicon formation. The various models describing Porous Silicon formation are reviewed and the known electrochemical and morphological properties are discussed with the intention of unifying the different models into a comprehensive explanation for the formation of a Porous structure in Silicon. Because the specific surface dissolution chemistry is critical for a complete understanding of pore formation, some of the more prominent dissolution reactions are also reviewed and their relative importance to pore generation and morphology is discussed. Some aspects of the recently reported quantum effects are also reviewed. Because the mechanism of Porous Silicon formation involves a wide range of interdisciplinary fields, a considerable number of analogies and examples to related phenomena ...
Lorenzo Pavesi - One of the best experts on this subject based on the ideXlab platform.
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Multiparametric Porous Silicon Sensors
Sensors, 2002Co-Authors: Camilla Baratto, C. Oton, Guido Faglia, Zeno Gaburro, Lucio Pancheri, Giorgio Sberveglieri, Lorenzo PavesiAbstract:We investigated the possibility of using several sensing parameters from Porous Silicon in order to improve gas selectivity. By fabricating Porous Silicon optical microcavities, three independent quantities can be measured, i.e. the electrical conductance, the photoluminescence intensity, and the wavelength of the optical resonance. We monitored the change of these three parameters as a function of NO2 (0.5-5 ppm), ethanol (300-15000 ppm) and relative humidity (0-100%). Preliminary results confirm that the examined species affect the parameters in a different way, both as a relative change and as dynamic.
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Controlled photon emission in Porous Silicon microcavities
Applied Physics Letters, 1995Co-Authors: Lorenzo Pavesi, Claudio Mazzoleni, Alessandro Tredicucci, Vittorio PellegriniAbstract:We demonstrate the preparation of narrow‐band Porous‐Silicon reflectors integrated on Porous‐Silicon layers by electrochemical etching. By carefully tuning the resulting photon cavity mode around the maximum of the Porous Silicon photoluminescence, we have obtained both a narrowing and enhancement of the emission line, and a highly concentrated radiation pattern. These results show that the Porous Silicon spontaneous emission is modified because of the coupling with the photon cavity mode.
