igor levitsky - Academia.edu (original) (raw)

Papers by igor levitsky

Chemical Physics Letters, Feb 1, 1993

ACS Applied Electronic Materials, 2019

Nanotechnology, Jan 6, 2016

We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amo... more We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amorphous silicon (a-Si). The high quality carbon nanotube network was dry transferred onto intrinsic a-Si forming Schottky junction for metallic SWNT bundles and heterojunctions for semiconducting SWNT bundles. The nanotube chemical doping and a-Si surface treatment minimized the hysteresis effect in current-voltage characteristics allowing an increase in the conversion efficiency to 1.5% under an air mass 1.5 solar spectrum simulator. We demonstrated that the thin SWNT film is able to replace a simultaneously p-doped a-Si layer and transparent conductive electrode in conventional amorphous silicon thin film photovoltaics.

Journal of Nanomedicine & Nanotechnology, 2012

Journal of the American Chemical Society, 1999

The Journal of the Acoustical Society of America, 2012

Journal of Applied Polymer Science, 2010

A sensor and dosimeter specific to inorganic and organic amine bases composed of Rhodamine B diss... more A sensor and dosimeter specific to inorganic and organic amine bases composed of Rhodamine B dissolved in Nafion is prepared and evaluated. UV‐vis, emission, and IR spectroscopies are used to monitor the presence of a variety of analytes, including aliphatic and aromatic amines. The Rhodamine B serves as a visual indicator of the presence of an analyte by turning from brown to pink upon exposure to aliphatic amines after sufficient exposure, thus acting as a visual monitor. The Rhodamine B also acts as a fluorescent sensor, which turns on upon exposure to the analyte. The sulfonic acid groups in the Nafion protonate the bases, giving unique signatures in the IR spectra allowing for differentiation of the bases. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Applied Physics Letters, 2007

Conjugated polymers entrapped in porous silicon microcavity have been studied as optical sensors ... more Conjugated polymers entrapped in porous silicon microcavity have been studied as optical sensors for low volatility explosives such as trinitrotoluene. The fluorescence spectra of entrapped polymers were modulated by the microcavity via a spectral “hole” that matches the resonance peak of the microcavity reflectance. Exposure of the porous silicon microcavity containing entrapped polymer to explosives vapor results in a red shift of the resonance peak and the spectral hole, accompanied by the quenching of the fluorescence. This multiplexed response provides multiple monitoring parameters, enabling the development of an optical sensor array for the detection of target explosive vapor.

Advanced Functional Materials, 2012

ABSTRACT An anisotropic carbon nanotube (CNT)-polymer composite for bolometric applications in th... more ABSTRACT An anisotropic carbon nanotube (CNT)-polymer composite for bolometric applications in the mid-IR spectral range (2.5–20 μm) is studied. Composite alignment in conjunction with non-uniform distribution of CNTs in the polymer matrix allows for a significant enhancement of the temperature coefficient of resistance (0.82% K−1) with respect to uniform composite (0.24% K−1). As a result a responsivity of ≈ 500 V W−1 is reached, which is the highest for CNT-based bolometers reported to date. Such remarkable optical and thermal characteristics are explained in terms of fluctuation tunneling theory taking into account the composite anisotropy and the gradient of the CNT concentration. Flatness of the photoresponse in the broad spectral mid-IR range and enhanced responsivity provide a great potential for the use of such novel composite for applications in IR spectroscopy and thermal imaging.

Optical humidity sensing and ultrasound effect for mesoporous silicon one-dimensional

Summaries of Papers Presented at the Lasers and Electro-Optics. CLEO '02. Technical Diges

Summary form only given. In this work, we investigate organic-inorganic nanocomposite arrays for ... more Summary form only given. In this work, we investigate organic-inorganic nanocomposite arrays for applications in future nano-photonics. We report on the drastic difference in absorption spectrum between the rhodamine-in-nanopore array and the more conventional rhodamine film-on-glass setting, and on the many-fold increase of the fluorescence yield in the former. The experimental findings not only highlight the great benefits in forming organic-inorganic nanocomposite arrays for high yield, broadly tunable light emission/detection and nonlinear optics but also offer insights into the self-assembling (aggregation) and energy transport mechanisms of molecules in highly confined, highly anisotropic nanoscale pores.

Photophysics of Carbon Nanotubes Interfaced with Organic and Inorganic Materials

We present a new thin-film solar cell structure in which the traditional transparent conductive o... more We present a new thin-film solar cell structure in which the traditional transparent conductive oxide electrode (ZnO) is replaced by a transparent conductive coating consisting of a network of bundled single-wall carbon nanotubes. Optical transmission properties of these coatings are presented in relation to their electrical properties (sheet resistance), along with preliminary solar cell results from devices made using CuIn1-xGaxSe2 thinfilm absorber materials. Achieving an energy conversion efficiency of >12% and a quantum efficiency of ~80% demonstrate the feasibility of the concept. A discussion of the device structures will be presented considering the physical properties of the new electrodes comparing current-voltage results from the new solar cell structure and those from standard ZnO/CdS/Cu(In,Ga)Se2/Mo solar cells.

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IEEE Nanotechnology Magazine

Nanomaterials Application Properties 2013, Jun 17, 2013

Chemical Physics Letters, Feb 1, 1993

ACS Applied Electronic Materials, 2019

Nanotechnology, Jan 6, 2016

We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amo... more We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amorphous silicon (a-Si). The high quality carbon nanotube network was dry transferred onto intrinsic a-Si forming Schottky junction for metallic SWNT bundles and heterojunctions for semiconducting SWNT bundles. The nanotube chemical doping and a-Si surface treatment minimized the hysteresis effect in current-voltage characteristics allowing an increase in the conversion efficiency to 1.5% under an air mass 1.5 solar spectrum simulator. We demonstrated that the thin SWNT film is able to replace a simultaneously p-doped a-Si layer and transparent conductive electrode in conventional amorphous silicon thin film photovoltaics.

Journal of Nanomedicine & Nanotechnology, 2012

Journal of the American Chemical Society, 1999

The Journal of the Acoustical Society of America, 2012

Journal of Applied Polymer Science, 2010

A sensor and dosimeter specific to inorganic and organic amine bases composed of Rhodamine B diss... more A sensor and dosimeter specific to inorganic and organic amine bases composed of Rhodamine B dissolved in Nafion is prepared and evaluated. UV‐vis, emission, and IR spectroscopies are used to monitor the presence of a variety of analytes, including aliphatic and aromatic amines. The Rhodamine B serves as a visual indicator of the presence of an analyte by turning from brown to pink upon exposure to aliphatic amines after sufficient exposure, thus acting as a visual monitor. The Rhodamine B also acts as a fluorescent sensor, which turns on upon exposure to the analyte. The sulfonic acid groups in the Nafion protonate the bases, giving unique signatures in the IR spectra allowing for differentiation of the bases. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Applied Physics Letters, 2007

Conjugated polymers entrapped in porous silicon microcavity have been studied as optical sensors ... more Conjugated polymers entrapped in porous silicon microcavity have been studied as optical sensors for low volatility explosives such as trinitrotoluene. The fluorescence spectra of entrapped polymers were modulated by the microcavity via a spectral “hole” that matches the resonance peak of the microcavity reflectance. Exposure of the porous silicon microcavity containing entrapped polymer to explosives vapor results in a red shift of the resonance peak and the spectral hole, accompanied by the quenching of the fluorescence. This multiplexed response provides multiple monitoring parameters, enabling the development of an optical sensor array for the detection of target explosive vapor.

Advanced Functional Materials, 2012

ABSTRACT An anisotropic carbon nanotube (CNT)-polymer composite for bolometric applications in th... more ABSTRACT An anisotropic carbon nanotube (CNT)-polymer composite for bolometric applications in the mid-IR spectral range (2.5–20 μm) is studied. Composite alignment in conjunction with non-uniform distribution of CNTs in the polymer matrix allows for a significant enhancement of the temperature coefficient of resistance (0.82% K−1) with respect to uniform composite (0.24% K−1). As a result a responsivity of ≈ 500 V W−1 is reached, which is the highest for CNT-based bolometers reported to date. Such remarkable optical and thermal characteristics are explained in terms of fluctuation tunneling theory taking into account the composite anisotropy and the gradient of the CNT concentration. Flatness of the photoresponse in the broad spectral mid-IR range and enhanced responsivity provide a great potential for the use of such novel composite for applications in IR spectroscopy and thermal imaging.

Optical humidity sensing and ultrasound effect for mesoporous silicon one-dimensional

Summaries of Papers Presented at the Lasers and Electro-Optics. CLEO '02. Technical Diges

Summary form only given. In this work, we investigate organic-inorganic nanocomposite arrays for ... more Summary form only given. In this work, we investigate organic-inorganic nanocomposite arrays for applications in future nano-photonics. We report on the drastic difference in absorption spectrum between the rhodamine-in-nanopore array and the more conventional rhodamine film-on-glass setting, and on the many-fold increase of the fluorescence yield in the former. The experimental findings not only highlight the great benefits in forming organic-inorganic nanocomposite arrays for high yield, broadly tunable light emission/detection and nonlinear optics but also offer insights into the self-assembling (aggregation) and energy transport mechanisms of molecules in highly confined, highly anisotropic nanoscale pores.

Photophysics of Carbon Nanotubes Interfaced with Organic and Inorganic Materials

We present a new thin-film solar cell structure in which the traditional transparent conductive o... more We present a new thin-film solar cell structure in which the traditional transparent conductive oxide electrode (ZnO) is replaced by a transparent conductive coating consisting of a network of bundled single-wall carbon nanotubes. Optical transmission properties of these coatings are presented in relation to their electrical properties (sheet resistance), along with preliminary solar cell results from devices made using CuIn1-xGaxSe2 thinfilm absorber materials. Achieving an energy conversion efficiency of >12% and a quantum efficiency of ~80% demonstrate the feasibility of the concept. A discussion of the device structures will be presented considering the physical properties of the new electrodes comparing current-voltage results from the new solar cell structure and those from standard ZnO/CdS/Cu(In,Ga)Se2/Mo solar cells.

[

IEEE Nanotechnology Magazine

Nanomaterials Application Properties 2013, Jun 17, 2013