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174 results on '"Dehm, Simone"'

1. Raman Fingerprints of Graphene Produced by Anodic Electrochemical Exfoliation

Author

Nagyte, Vaiva, Kelly, Daniel J., Felten, Alexandre, Picardi, Gennaro, Shin, YuYoung, Alieva, Adriana, Worsley, Robyn E., Parvez, Khaled, Dehm, Simone, Krupke, Ralph, Haigh, Sarah J., Oikonomou, Antonios, Pollard, Andrew J., and Casiraghi, Cinzia

Subjects
Physics - Applied Physics, Condensed Matter - Materials Science
Abstract

Electrochemical exfoliation is one of the most promising methods for scalable production of graphene. However, limited understanding of its Raman spectrum as well as lack of measurement standards for graphene strongly limit its industrial applications. In this work we show a systematic study of the Raman spectrum of electrochemically exfoliated graphene, produced using different electrolytes and different types of solvents in varying amounts. We demonstrate that no information on the thickness can be extracted from the shape of the 2D peak as this type of graphene is defective. Furthermore, the number of defects and the uniformity of the samples strongly depend on the experimental conditions, including post-processing. Under specific conditions, formation of short conductive trans-polyacetylene chains has been observed. Our Raman analysis provides guidance for the community on how to get information on defects coming from electrolyte, temperature and other experimental conditions, by making Raman spectroscopy a powerful metrology tool., Comment: This document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in Nano Letters, American Chemical Society after peer review. To access the final edited and published work, included the SI, see DOI: 10.1021/acs.nanolett.0c00332

Published
2020
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2. Low-temperature electroluminescence excitation mapping of excitons and trions in short channel monochiral carbon nanotube device

Author

Gaulke, Marco, Janissek, Alexander, Peyyety, Naga Anirudh, Alamgir, Imtiaz, Riaz, Adnan, Dehm, Simone, Li, Han, Lemmer, Uli, Flavel, Benjamin S., Kappes, Manfred M., Hennrich, Frank, Wei, Li, Chen, Yuan, Pyatkov, Felix, and Krupke, Ralph

Subjects
Physics - Applied Physics, Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Single walled carbon nanotubes as emerging quantum-light sources may fill a technological gap in silicon photonics due to their potential use as near infrared, electrically driven, classical or non-classical emitters. Unlike in photoluminescence, where nanotubes are excited with light, electrical excitation of single tubes is challenging and heavily influenced by device fabrication, architecture and biasing conditions. Here we present electroluminescence spectroscopy data of ultra short channel devices made from (9,8) carbon nanotubes emitting in the telecom band. Emissions are stable under current biasing and no quenching is observed down to 10 nm gap size. Low-temperature electroluminescence spectroscopy data also reported exhibits cold emission and linewidths down to 2 meV at 4 K. Electroluminescence excitation maps give evidence that carrier recombination is the mechanism for light generation in short channels. Excitonic and trionic emissions can be switched on and off by gate voltage and corresponding emission efficiency maps were compiled. Insights are gained into the influence of acoustic phonons on the linewidth, absence of intensity saturation and exciton exciton annihilation, environmental effects like dielectric screening and strain on the emission wavelength, and conditions to suppress hysteresis and establish optimum operation conditions.

Published
2019

3. Light emission, light detection and strain sensing with nanocrystalline graphene

Author

Riaz, Adnan, Pyatkov, Feliks, Alam, Asiful, Dehm, Simone, Felten, Alexandre, Chakravadhanula, Venkata S. K., Flavel, Benjamin S., Kübel, Christian, Lemmer, Uli, and Krupke, Ralph

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Graphene is of increasing interest for optoelectronic applications exploiting light detection, light emission and light modulation. Intrinsically light matter interaction in graphene is of a broadband type. However by integrating graphene into optical micro cavities also narrow band light emitters and detectors have been demonstrated. The devices benefit from the transparency, conductivity and processability of the atomically thin material. To this end we explore in this work the feasibility of replacing graphene by nanocrystalline graphene, a material which can be grown on dielectric surfaces without catalyst by graphitization of polymeric films. We have studied the formation of nanocrystalline graphene on various substrates and under different graphitization conditions. The samples were characterized by resistance, optical transmission, Raman, X-ray photoelectron spectroscopy, atomic force microscopy and electron microscopy measurements. The conducting and transparent wafer-scale material with nanometer grain size was also patterned and integrated into devices for studying light-matter interaction. The measurements show that nanocrystalline graphene can be exploited as an incandescent emitter and bolometric detector similar to crystalline graphene. Moreover the material exhibits piezoresistive behavior which makes nanocrystalline graphene interesting for transparent strain sensors.

Published
2016
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5. Vanishing Hysteresis in Carbon Nanotube Transistors Embedded in Boron Nitride/Polytetrafluoroethylene Heterolayers

Author

Kumar, Sandeep, Dagli, Daghan, Dehm, Simone, Das, Chittaranjan, Wei, Li, Chen, Yuan, Hennrich, Frank, Krupke, Ralph, Kumar, Sandeep, Dagli, Daghan, Dehm, Simone, Das, Chittaranjan, Wei, Li, Chen, Yuan, Hennrich, Frank, and Krupke, Ralph

Abstract

Carbon nanotube field‐effect transistors fabricated on silicon wafers with thermal oxide often suffer from large gate‐voltage hysteresis, induced by charge trapping sites in oxides, surface hydroxyl groups, and the presence of water molecules. Surface functionalization and passivation, as well as vacuum annealing and reduced operating temperature, have shown to diminish or even eliminate hysteresis. Herein, the fabrication of nearly hysteresis‐free transistors on Si/SiO₂ by embedding carbon nanotubes and the connecting electrodes in a hexagonal boron nitride (h‐BN) bottom layer and a polytetrafluoroethylene (PTFE) top layer is demonstrated. The conditions at which catalyst‐free synthesis of h‐BN on SiO₂/Si with borazine is obtained, and the subsequent liquid‐phase deposition of PTFE, are discussed. Device transfer curves are measured before and after PTFE deposition. It is found that the hysteresis is reduced after PTFE deposition, but vanishes only after a waiting period of several days. Simultaneously, the on‐state current increases with time. The results give evidence for the absence of trap states in h‐BN/PTFE heterolayers and a high breakthrough field strength in those wafer‐scalable materials.

Published
2024

6. Enhanced Broadband Photodetection with Geometry and Interface Engineered Nanocrystalline Graphite

Author

Parmar, Devang, Dehm, Simone, Peyyety, Naga Anirudh, Kumar, Sandeep, Krupke, Ralph, Parmar, Devang, Dehm, Simone, Peyyety, Naga Anirudh, Kumar, Sandeep, and Krupke, Ralph

Abstract

Photodetection across the near‐infrared (NIR) to short‐wavelength infrared (SWIR) spectrum is important for many applications. This study explores photodetection using nanocrystalline graphite (NCG) in a suspended, narrow constriction configuration for improved performance. Bowtie constrictions are fabricated in both suspended and substrate‐supported NCG devices, allowing for accurate comparison. It shows that the suspended constriction enhances the bolometric photoresponse and sensor detectivity by several orders of magnitude compared to the substrate‐supported counterparts, attributed to reduced thermalization and electric field concentration. The suspended configuration preserves a spectrally flat photoresponse while reducing operating voltage through a tailored NCG layer thickness. Chromatic aberration‐corrected photocurrent spectroscopy is used to measure the photoresponse from 1100 to 1700 nm, and diffraction‐limited hyperspectral photocurrent imaging is conducted to measure the local photocurrent generation across the device. Bolometric and photo‐thermoelectric currents are restricted to the suspended central constriction due to electric field concentration and thermal decoupling and the direction of the photocurrents within the sensor is revealed. The experimental data is complemented by simulations of the light absorption and the electric field distribution. This work indicates the importance of geometry and thermal decoupling for boosting device performance, offering promising prospects for sensitive and low‐power NCG‐based photodetectors in the NIR‐SWIR range.

Published
2024

7. Sensitive Detection of a Gaseous Analyte with Low‐Power Metal–Organic Framework Functionalized Carbon Nanotube Transistors

Author

Kumar, Sandeep, Dehm, Simone, Wieland, Laura, Chandresh, Abhinav, Heinke, Lars, Flavel, Benjamin S., Krupke, Ralph, Kumar, Sandeep, Dehm, Simone, Wieland, Laura, Chandresh, Abhinav, Heinke, Lars, Flavel, Benjamin S., and Krupke, Ralph

Abstract

A highly sensitive and low‐power sensing platform for detecting ethanol molecules by interfacing high‐purity, large‐diameter semiconducting carbon nanotube transistors with a metal–organic framework layer is presented. The new devices outperform similar graphene‐based metal–organic framework devices by several orders of magnitude in terms of sensitivity and power consumption, and can detect extremely low ethanol concentrations down to sub‐ppb levels while consuming only picowatts of power. The exceptional sensor performance results from the nanotube transistor's high on/off ratio and its sensitivity to charges, allowing for ultra‐low power consumption. The platform can also compensate for shifts in threshold voltage induced by ambient conditions, making it suitable for use in humid air. This novel concept of MOF/CNTFETs could be customized for detecting various gaseous analytes, leading to a range of ultra‐sensitive and ultra‐low power sensors.

Published
2024

8. Graphitizability of Polymer Thin Films: An In Situ TEM Study of Thickness Effects on Nanocrystalline Graphene/Glassy Carbon Formation

Author

Shyam Kumar, C. N., Possel, Clemens, Dehm, Simone, Chakravadhanula, Venkata Sai Kiran, Wang, Di, Wenzel, Wolfgang, Krupke, Ralph, Kübel, Christian, Shyam Kumar, C. N., Possel, Clemens, Dehm, Simone, Chakravadhanula, Venkata Sai Kiran, Wang, Di, Wenzel, Wolfgang, Krupke, Ralph, and Kübel, Christian

Abstract

Polymer pyrolysis has emerged as a versatile method to synthesize graphenoid (graphene like) materials with varying thickness and properties. The morphology of the thin film, especially the thickness, greatly affects the graphitizability and the properties of the graphenoid material. Using in situ current annealing inside a transmission electron microscope (TEM), the thickness‐dependent structural evolution of the polymer film with a special focus on thickness effects is followed. At high temperatures, thin samples form large graphene layers oriented parallel to the substrate, whereas in thick samples multi‐walled cage‐like structures are formed. Moleclar Dynamics (MD) simulations reveal a film thickness of 40 Å below which, the carbonized layers align parallel to the surface. For thicker samples, the orientation of the layers becomes increasingly misoriented starting from the surface to the center. This structural change can be attributed to the formation of bonded multi‐layers from the initially unsaturated activated edges. The resulting cage‐like structures are stable even during simulated annealing at temperatures as high as 3500 K. An atomistic understanding of the formation of these structures is presented. The results clearly indicate the critical effect of thickness on the graphitizability of polymers and provide a new understanding of the structural evolution during pyrolysis.

Published
2024

9. Electroluminescence from chirality-sorted (9,7)-semiconducting carbon nanotube devices

Author

Pfeiffer, Martin H. P., Stürzl, Ninette, Marquardt, Christoph W., Engel, Michael, Dehm, Simone, Hennrich, Frank, Kappes, Manfred M., Lemmer, Uli, and Krupke, Ralph

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Optics
Abstract

We have measured the electroluminescence and photoluminescence of (9,7) semiconducting carbon nanotube devices and demonstrate that the electroluminescence wavelength is determined by the nanotube's chiral index (n,m). The devices were fabricated on Si3N4 membranes by dielectrophoretic assembly of tubes from monochiral dispersion. Electrically driven (9,7) devices exhibit a single Lorentzian shaped emission peak at 825 nm in the visible part of the spectrum. The emission could be assigned to the excitonic E22 interband transition by comparison of the electroluminescence spectra with corresponding photoluminescence excitation maps. We show a linear dependence of the EL peak width on the electrical current, and provide evidence for the inertness of Si3N4 surfaces with respect to the nanotubes optical properties., Comment: 6 pages, 3 figures, submitted to Optics Express

Published
2011
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10. Dielectrophoretic Assembly of High-Density Arrays of Individual Graphene Devices for Rapid Screening

Author

Vijayaraghavan, Aravind, Sciascia, Calogero, Dehm, Simone, Lombardo, Antonio, Bonetti, Alessandro, Ferrari, Andrea C., and Krupke, Ralph

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract

We establish the use of dielectrophoresis for the directed parallel assembly of individual flakes and nanoribbons of few-layer graphene into electronic devices. This is a bottom-up approach where source and drain electrodes are prefabricated and the flakes are deposited from a solution using an alternating electric field applied between the electrodes. These devices are characterized by scanning electron microscopy, atomic force microscopy, Raman spectroscopy and electron transport measurements. They are shown to be electrically active and their current carrying capacity and subsequent failure mechanism is revealed. Akin to carbon nanotubes, we show that the dielectrophoretic deposition is self-limiting to one flake per device and is scalable to ultra-large-scale integration densities, thereby enabling the rapid screening of a large number of devices., Comment: ACS Nano, (2009) In Press

Published
2009
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14. (Invited) Electroluminescence from Single-Walled Carbon Nanotubes with Quantum Defects

Author

Li, Min-Ken, primary, Riaz, Adnan, additional, Wederhake, Martina, additional, Fink, Karin, additional, Saha, Avishek, additional, Dehm, Simone, additional, He, Xiaowei, additional, Schoeppler, Friedrich, additional, Kappes, Manfred, additional, Htoon, Han, additional, Popov, Valentin, additional, Doorn, Stephen, additional, Hertel, Tobias, additional, Hennrich, Frank, additional, and Krupke, Ralph, additional

Published
2023
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16. Sensing Molecules with Metal–Organic Framework Functionalized Graphene Transistors

Author

Kumar, Sandeep, Pramudya, Yohanes, Müller, Kai, Chandresh, Abhinav, Dehm, Simone, Heidrich, Shahriar, Fediai, Artem, Parmar, Devang, Perera, Delwin, Rommel, Manuel, Heinke, Lars, Wenzel, Wolfgang, Wöll, Christof, Krupke, Ralph, Kumar, Sandeep, Pramudya, Yohanes, Müller, Kai, Chandresh, Abhinav, Dehm, Simone, Heidrich, Shahriar, Fediai, Artem, Parmar, Devang, Perera, Delwin, Rommel, Manuel, Heinke, Lars, Wenzel, Wolfgang, Wöll, Christof, and Krupke, Ralph

Abstract

Graphene is inherently sensitive to vicinal dielectrics and local charge distributions, a property that can be probed by the position of the Dirac point in graphene field‐effect transistors. Exploiting this as a useful sensing principle requires selectivity; however, graphene itself exhibits no molecule‐specific interaction. Complementarily, metal–organic frameworks can be tailored to selective adsorption of specific molecular species. Here, a selective ethanol sensor is demonstrated by growing a surface‐mounted metal–organic framework (SURMOF) directly onto graphene field‐effect transistors (GFETs). Unprecedented shifts of the Dirac point, as large as 15 V, are observed when the SURMOF/GFET is exposed to ethanol, while a vanishingly small response is observed for isopropanol, methanol, and other constituents of the air, including water. The synthesis and conditioning of the hybrid materials sensor with its functional characteristics are described and a model is proposed to explain the origin, magnitude, and direction of the Dirac point voltage shift. Tailoring multiple SURMOFs to adsorb specific gases on an array of such devices thus generates a versatile, selective, and highly sensitive platform for sensing applications.

Published
2023

17. Electroluminescence from Single-Walled Carbon Nanotubes with Quantum Defects

Author

Li, Min-Ken, primary, Riaz, Adnan, additional, Wederhake, Martina, additional, Fink, Karin, additional, Saha, Avishek, additional, Dehm, Simone, additional, He, Xiaowei, additional, Schöppler, Friedrich, additional, Kappes, Manfred M., additional, Htoon, Han, additional, Popov, Valentin N., additional, Doorn, Stephen K., additional, Hertel, Tobias, additional, Hennrich, Frank, additional, and Krupke, Ralph, additional

Published
2022
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21. Sensing Molecules with Metal–Organic Framework Functionalized Graphene Transistors

Author

Kumar, Sandeep, primary, Pramudya, Yohanes, additional, Müller, Kai, additional, Chandresh, Abhinav, additional, Dehm, Simone, additional, Heidrich, Shahriar, additional, Fediai, Artem, additional, Parmar, Devang, additional, Perera, Delwin, additional, Rommel, Manuel, additional, Heinke, Lars, additional, Wenzel, Wolfgang, additional, Wöll, Christof, additional, and Krupke, Ralph, additional

Published
2021
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23. Vanishing Hysteresis in Carbon Nanotube Transistors Embedded in Boron Nitride/Polytetrafluoroethylene Heterolayers

Author

Kumar, Sandeep, Dagli, Daghan, Dehm, Simone, Das, Chittaranjan, Wei, Li, Chen, Yuan, Hennrich, Frank, and Krupke, Ralph

Subjects
Technology, ddc:600
Abstract

Carbon nanotube field‐effect transistors fabricated on silicon wafers with thermal oxide often suffer from large gate‐voltage hysteresis, induced by charge trapping sites in oxides, surface hydroxyl groups, and the presence of water molecules. Surface functionalization and passivation, as well as vacuum annealing and reduced operating temperature, have shown to diminish or even eliminate hysteresis. Herein, the fabrication of nearly hysteresis‐free transistors on Si/SiO$_{2}$ by embedding carbon nanotubes and the connecting electrodes in a hexagonal boron nitride (h‐BN) bottom layer and a polytetrafluoroethylene (PTFE) top layer is demonstrated. The conditions at which catalyst‐free synthesis of h‐BN on SiO$_{2}$/Si with borazine is obtained, and the subsequent liquid‐phase deposition of PTFE, are discussed. Device transfer curves are measured before and after PTFE deposition. It is found that the hysteresis is reduced after PTFE deposition, but vanishes only after a waiting period of several days. Simultaneously, the on‐state current increases with time. The results give evidence for the absence of trap states in h‐BN/PTFE heterolayers and a high breakthrough field strength in those wafer‐scalable materials.

Published
2020

24. Low-Temperature Electroluminescence Excitation Mapping of Excitons and Trions in Short-Channel Monochiral Carbon Nanotube Devices

Author

Gaulke, Marco, Janissek, Alexander, Peyyety, Naga Anirudh, Alamgir, Imtiaz, Riaz, Adnan, Dehm, Simone, Li, Han, Lemmer, Uli, Flavel, Benjamin S., Kappes, Manfred M., Hennrich, Frank, Wei, Li, Chen, Yuan, Pyatkov, Felix, and Krupke, Ralph

Subjects
Condensed Matter::Materials Science, Technology, ddc:600
Abstract

Single-walled carbon nanotubes as emerging quantum-light sources may fill a technological gap in silicon photonics due to their potential use as near-infrared, electrically driven, classical or nonclassical emitters. Unlike in photoluminescence, where nanotubes are excited with light, electrical excitation of single tubes is challenging and heavily influenced by device fabrication, architecture, and biasing conditions. Here we present electroluminescence spectroscopy data of ultra-short-channel devices made from (9,8) carbon nanotubes emitting in the telecom band. Emissions are stable under current biasing, and no enhanced suppression is observed down to 10 nm gap size. Low-temperature electroluminescence spectroscopy data also reported exhibit cold emission and line widths down to 2 meV at 4 K. Electroluminescence excitation maps give evidence that carrier recombination is the mechanism for light generation in short channels. Excitonic and trionic emissions can be switched on and off by gate voltage, and corresponding emission efficiency maps were compiled. Insights are gained into the influence of acoustic phonons on the line width, absence of intensity saturation and exciton���exciton annihilation, environmental effects such as dielectric screening and strain on the emission wavelength, and conditions to suppress hysteresis and establish optimum operation conditions.

Published
2020

25. Ionic liquid gating of single-walled carbon nanotube devices with ultra-short channel length down to 10 nm

Author

Janissek, Alexander, primary, Lenz, Jakob, additional, Giudice, Fabio del, additional, Gaulke, Marco, additional, Pyatkov, Felix, additional, Dehm, Simone, additional, Hennrich, Frank, additional, Wei, Li, additional, Chen, Yuan, additional, Fediai, Artem, additional, Kappes, Manfred, additional, Wenzel, Wolfgang, additional, Krupke, Ralph, additional, and Weitz, R. Thomas, additional

Published
2021
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27. (Invited) Low-Temperature Electroluminescence Excitation Mapping of Excitons and Trions in Short-Channel Monochiral Carbon Nanotube Devices

Author

Gaulke, Marco, primary, Peyyety, Naga Anirudh, additional, Alamgir, Imtiaz, additional, Riaz, Adnan, additional, Dehm, Simone, additional, Li, Han, additional, Lemmer, Ulrich, additional, Flavel, Benjamin S., additional, Kappes, Manfred, additional, Hennrich, Frank, additional, Wei, Li, additional, Chen, Yuan, additional, Pyatkov, Felix, additional, and Krupke, Ralph, additional

Published
2020
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28. Raman Fingerprints of Graphene Produced by Anodic Electrochemical Exfoliation

Author

Nagyte, Vaiva, primary, Kelly, Daniel J., additional, Felten, Alexandre, additional, Picardi, Gennaro, additional, Shin, YuYoung, additional, Alieva, Adriana, additional, Worsley, Robyn E., additional, Parvez, Khaled, additional, Dehm, Simone, additional, Krupke, Ralph, additional, Haigh, Sarah J., additional, Oikonomou, Antonios, additional, Pollard, Andrew J., additional, and Casiraghi, Cinzia, additional

Published
2020
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29. Separation of Specific Single-Enantiomer Single-Wall Carbon Nanotubes in the Large-Diameter Regime

Author

Li, Han, primary, Gordeev, Georgy, additional, Garrity, Oisin, additional, Peyyety, Naga Anirudh, additional, Selvasundaram, Pranauv Balaji, additional, Dehm, Simone, additional, Krupke, Ralph, additional, Cambré, Sofie, additional, Wenseleers, Wim, additional, Reich, Stephanie, additional, Zheng, Ming, additional, Fagan, Jeffrey A., additional, and Flavel, Benjamin S., additional

Published
2019
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37. Formation of nanocrystalline graphene on germanium

Author

Yekani, Rana, primary, Rusak, Evgenia, additional, Riaz, Adnan, additional, Felten, Alexandre, additional, Breitung, Ben, additional, Dehm, Simone, additional, Perera, Delwin, additional, Rohrer, Jochen, additional, Rockstuhl, Carsten, additional, and Krupke, Ralph, additional

Published
2018
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41. Photocurrent spectroscopy of dye-sensitized carbon nanotubes

Author

Alam, Asiful, primary, Dehm, Simone, additional, Hennrich, Frank, additional, Zakharko, Yuriy, additional, Graf, Arko, additional, Pfohl, Moritz, additional, Hossain, Ihteaz M., additional, Kappes, Manfred M., additional, Zaumseil, Jana, additional, Krupke, Ralph, additional, and Flavel, Benjamin S., additional

Published
2017
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44. Separation of Specific Single-Enantiomer Single-Wall Carbon Nanotubes in the Large-Diameter Regime

Author

Li, Han, Gordeev, Georgy, Garrity, Oisin, Peyyety, Naga Anirudh, Selvasundaram, Pranauv Balaji, Dehm, Simone, Krupke, Ralph, Cambré, Sofie, Wenseleers, Wim, Reich, Stephanie, Zheng, Ming, Fagan, Jeffrey A., and Flavel, Benjamin S.

Abstract

The enantiomer-level isolation of single-walled carbon nanotubes (SWCNTs) in high concentration and with high purity for nanotubes greater than 1.1 nm in diameter is demonstrated using a two-stage aqueous two-phase extraction (ATPE) technique. In total, five different nanotube species of ∼1.41 nm diameter are isolated, including both metallics and semiconductors. We characterize these populations by absorbance spectroscopy, circular dichroism spectroscopy, resonance Raman spectroscopy, and photoluminescence mapping, revealing and substantiating mod-dependent optical dependencies. Using knowledge of the competitive adsorption of surfactants to the SWCNTs that controls partitioning within the ATPE separation, we describe an advanced acid addition methodology that enables the fine control of the separation of these select nanotubes. Furthermore, we show that endohedral filling is a previously unrecognized but important factor to ensure a homogeneous starting material and further enhance the separation yield, with the best results for alkane-filled SWCNTs, followed by empty SWCNTs, with the intrinsic inhomogeneity of water-filled SWCNTs causing them to be worse for separations. Lastly, we demonstrate the potential use of these nanotubes in field-effect transistors.

Published
2020
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46. Employing Microwave Graphene Field Effect Transistors for Infrared Radiation Detection.

Author

Antonio Benfante, Giambra, Marco A., Pernice, Riccardo, Stivala, Salvatore, Calandra, Enrico, Parisi, Antonino, Cino, Alfonso C., Dehm, Simone, Danneau, Romain, Krupke, Ralph, and Busacca, Alessandro C.

Abstract

In this work, we investigate the possibility of employing graphene field effect transistors, specifically designed for microwave applications, as infrared detectors for telecom applications. Our devices have been fabricated on a sapphire substrate employing CVD-grown transferred graphene. The roles of both the gate dielectric and the DC bias conditions have been evaluated in order to maximize the infrared generated signal through an experimental investigation of the signal-to-noise ratio dependence on the transistor operating point. [ABSTRACT FROM AUTHOR]

Published
2018
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