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Full-Text Articles in Nanoscience and Nanotechnology

Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen Nov 2018

Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen

Mechanical Engineering Publications

Flexible graphene electronics are rapidly gaining interest, but their widespread implementation has been impeded by challenges with ink preparation, ink printing, and post-print annealing processes. Laser-induced graphene (LIG) promises a facile alternative by creating flexible graphene electronics on polyimide substrates through a one-step laser writing fabrication method. Herein we demonstrate the use of LIG, created through a low-cost UV laser, for electrochemical ion selective sensing of plant-available nitrogen (i.e., both ammonium and nitrate ions: NH4+ and NO3-) in soil samples. The laser used to create the LIG was operated at distinct pulse rates (10, 20, 30, 40, and 50 ...


Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen Oct 2018

Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen

Jonathan C. Claussen

Flexible graphene electronics are rapidly gaining interest, but their widespread implementation has been impeded by challenges with ink preparation, ink printing, and post-print annealing processes. Laser-induced graphene (LIG) promises a facile alternative by creating flexible graphene electronics on polyimide substrates through a one-step laser writing fabrication method. Herein we demonstrate the use of LIG, created through a low-cost UV laser, for electrochemical ion selective sensing of plant-available nitrogen (i.e., both ammonium and nitrate ions: NH4+ and NO3-) in soil samples. The laser used to create the LIG was operated at distinct pulse rates (10, 20, 30, 40, and 50 ...


Dynamical Thermal Conductivity Of Suspended Graphene Ribbons In The Hydrodynamic Regime, Zlatan Aksamija, Arnab K. Majee Jul 2018

Dynamical Thermal Conductivity Of Suspended Graphene Ribbons In The Hydrodynamic Regime, Zlatan Aksamija, Arnab K. Majee

Zlatan Aksamija

The steady-state behavior of thermal transport in bulk and nanostructured semiconductors has been widely
studied, both theoretically and experimentally. On the other hand, fast transients and frequency dynamics of
thermal conduction has been given less attention. The frequency response of thermal conductivity has become
more crucial in recent years, especially in light of the constant rise in the clock frequencies in microprocessors
and terahertz sensing applications. Thermal conductivity in response to a time-varying temperature field starts
decaying when the frequency exceeds a cutoff frequency Omega_c, which is related to the inverse of phonon relaxation time τ, on the order of ...


Printed Graphene Electrochemical Biosensors Fabricated By Inkjet Maskless Lithography For Rapid And Sensitive Detection Of Organophosphates, John A. Hondred, Joyce C. Breger, Nathan J. Alves, Scott A. Trammell, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen Mar 2018

Printed Graphene Electrochemical Biosensors Fabricated By Inkjet Maskless Lithography For Rapid And Sensitive Detection Of Organophosphates, John A. Hondred, Joyce C. Breger, Nathan J. Alves, Scott A. Trammell, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen

Jonathan C. Claussen

Solution phase printing of graphene-based electrodes has recently become an attractive low-cost, scalable manufacturing technique to create in-field electrochemical biosensors. Here we report a graphene-based electrode developed via Inkjet Maskless Lithography (IML) for the direct and rapid monitoring of triple-O linked phosphonate organophosphates (OPs); these constitute the active compounds found in chemical warfare agents and pesticides that exhibit acute toxicity as well as long-term pollution to soils and waterways. The IML printed graphene electrode is nano/microstructured with a 1000 mW benchtop laser engraver and electrochemically deposited platinum nanoparticles (dia. ~25 nm) to improve its electrical conductivity (sheet resistance decreased ...


A Paper Based Graphene-Nanocauliflower Hybrid Composite For Point Of Care Biosensing, S. L. Burrs, R. Sidhu, M. Bhargava, J. Kieman-Lewis, N. Schwalb, Y. Rong, Carmen Gomes, Jonathan C. Claussen, D. C. Vanegas, E. S. Mclamore Mar 2018

A Paper Based Graphene-Nanocauliflower Hybrid Composite For Point Of Care Biosensing, S. L. Burrs, R. Sidhu, M. Bhargava, J. Kieman-Lewis, N. Schwalb, Y. Rong, Carmen Gomes, Jonathan C. Claussen, D. C. Vanegas, E. S. Mclamore

Jonathan C. Claussen

Graphene paper has diverse applications in printed circuit board electronics, bioassays, 3D cell culture, and biosensing. Although development of nanometal-graphene hybrid composites is commonplace in the sensing literature, to date there are only a few examples of nanometal-decorated graphene paper for use in biosensing. In this manuscript, we demonstrate the synthesis and application of Pt nano cauliflower-functionalized graphene paper for use in electrochemical biosensing of small molecules (glucose, acetone, methanol) or detection of pathogenic bacteria (Escherichia coli O157:H7). Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy were used to show that graphene oxide deposited on nanocellulose crystals was ...


Printed Graphene Electrochemical Biosensors Fabricated By Inkjet Maskless Lithography For Rapid And Sensitive Detection Of Organophosphates, John A. Hondred, Joyce C. Breger, Nathan J. Alves, Scott A. Trammell, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen Mar 2018

Printed Graphene Electrochemical Biosensors Fabricated By Inkjet Maskless Lithography For Rapid And Sensitive Detection Of Organophosphates, John A. Hondred, Joyce C. Breger, Nathan J. Alves, Scott A. Trammell, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen

Mechanical Engineering Publications

Solution phase printing of graphene-based electrodes has recently become an attractive low-cost, scalable manufacturing technique to create in-field electrochemical biosensors. Here we report a graphene-based electrode developed via Inkjet Maskless Lithography (IML) for the direct and rapid monitoring of triple-O linked phosphonate organophosphates (OPs); these constitute the active compounds found in chemical warfare agents and pesticides that exhibit acute toxicity as well as long-term pollution to soils and waterways. The IML printed graphene electrode is nano/microstructured with a 1000 mW benchtop laser engraver and electrochemically deposited platinum nanoparticles (dia. ~25 nm) to improve its electrical conductivity (sheet resistance decreased ...


Suspended Graphene-Based Gas Sensor With 1-Mw Energy Consumption, Jong-Hyun Kim, Qin Zhou, Jiyoung Chang Jan 2017

Suspended Graphene-Based Gas Sensor With 1-Mw Energy Consumption, Jong-Hyun Kim, Qin Zhou, Jiyoung Chang

Mechanical & Materials Engineering Faculty Publications

This paper presents NH3 sensing with ultra-low energy consumption for fast recovery and a graphene sheet based on a suspended microheater. Sensitivity and repeatability are important characteristics of functional gas sensors embedded in mobile devices. Moreover, low energy consumption is an essential requirement in flexible and stretchable mobile electronics due to their small dimension and fluctuating resistivity during mechanical behavior. In this paper, we introduce a graphene-based ultra-low power gas detection device with integration of a suspended silicon heater. Dramatic power reduction is enabled by a duty cycle while not sacrificing sensitivity. The new oscillation method of heating improves ...


A Paper Based Graphene-Nanocauliflower Hybrid Composite For Point Of Care Biosensing, S. L. Burrs, R. Sidhu, M. Bhargava, J. Kieman-Lewis, N. Schwalb, Y. Rong, Carmen Gomes, Jonathan C. Claussen, D. C. Vanegas, E. S. Mclamore May 2016

A Paper Based Graphene-Nanocauliflower Hybrid Composite For Point Of Care Biosensing, S. L. Burrs, R. Sidhu, M. Bhargava, J. Kieman-Lewis, N. Schwalb, Y. Rong, Carmen Gomes, Jonathan C. Claussen, D. C. Vanegas, E. S. Mclamore

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Graphene paper has diverse applications in printed circuit board electronics, bioassays, 3D cell culture, and biosensing. Although development of nanometal-graphene hybrid composites is commonplace in the sensing literature, to date there are only a few examples of nanometal-decorated graphene paper for use in biosensing. In this manuscript, we demonstrate the synthesis and application of Pt nano cauliflower-functionalized graphene paper for use in electrochemical biosensing of small molecules (glucose, acetone, methanol) or detection of pathogenic bacteria (Escherichia coli O157:H7). Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy were used to show that graphene oxide deposited on nanocellulose crystals was ...


Mechanisms Controlling Friction And Adhesion At The Atomic Length-Scale, Xin Zhou Liu Jan 2015

Mechanisms Controlling Friction And Adhesion At The Atomic Length-Scale, Xin Zhou Liu

Publicly Accessible Penn Dissertations

A lack of understanding of the fundamental mechanisms governing atomic-scale adhesion and friction creates ongoing challenges as technologically-relevant devices are miniaturized. One major class of failure mechanisms of such devices results from high friction, adhesion, and wear. This thesis presents investigations into methods by which atomic-scale friction and adhesion can be controlled. Using atomic force microscopy (AFM), friction and adhesion properties of graphene were examined. While friction between the tip and graphene depends on thickness, as explained by the â??puckering effectâ??, adhesion is independent of the thickness when measured conventionally. However, adhesion is transiently higher when measured after the ...


Structural, Electronic And Catalytic Properties Of Graphene-Supported Platinum Nanoclusters, Ioanna Fampiou Aug 2014

Structural, Electronic And Catalytic Properties Of Graphene-Supported Platinum Nanoclusters, Ioanna Fampiou

Doctoral Dissertations

Carbon materials are predominantly used as catalytic supports due to their high surface area, excellent electrical conductivity, resistance to corrosion and structural stability. Graphene, a 2D monolayer of graphite, with its excellent thermal, electronic and mechanical features, has been considered a promising support material for next generation metal-graphene nanocatalysts. The main focus of this dissertation is to investigate the properties of such metal-graphene nanocomposites using computational methods, and to develop a comprehensive understanding of the experimentally observed enhanced catalytic activity of graphene-supported Platinum (Pt) clusters.

In particular, we seek to understand the role of graphene supports on the ground-state morphology ...


Nanomaterial-Mediated Biosensors For Monitoring Glucose, Eric S. Mclamore, Masashige Taguchi, Andre Ptitsyn, Jonathan C. Claussen Dec 2013

Nanomaterial-Mediated Biosensors For Monitoring Glucose, Eric S. Mclamore, Masashige Taguchi, Andre Ptitsyn, Jonathan C. Claussen

Jonathan C. Claussen

Real-time monitoring of physiological glucose transport is crucial for gaining new understanding of diabetes. Many techniques and equipment currently exist for measuring glucose, but these techniques are limited by complexity of the measurement, requirement of bulky equipment, and low temporal/spatial resolution. The development of various types of biosensors (eg, electrochemical, optical sensors) for laboratory and/or clinical applications will provide new insights into the cause(s) and possible treatments of diabetes. State-of-the-art biosensors are improved by incorporating catalytic nanomaterials such as carbon nanotubes, graphene, electrospun nanofibers, and quantum dots. These nanomaterials greatly enhance biosensor performance, namely sensitivity, response time ...


Graphene Decorated Substrates And Their Interfacial Characteristics, Anurag Kumar Oct 2013

Graphene Decorated Substrates And Their Interfacial Characteristics, Anurag Kumar

Open Access Dissertations

Carbon nanotubes and graphene have been extensively studied for their excellent properties. As research on carbon expands, two major issues face the scientific community: (i) Expanding the scale of synthesis and (ii) Integration of different carbon structures for improved functionality. While significant advancements have been made in large-scale synthesis, room for improvement remains. As the scale of production increases, issues such as time, cost and energy that may otherwise not be very significant, begin to play greater roles. Thus, in order to effectively transition from laboratory prototypes to industrial products, a synthesis method that can address these issues is strongly ...


Transparent Actuator Made With Few Layer Graphene Electrode And Dielectric Elastomer, For Variable Focus Lens, Taeseon Hwang, Hyeok-Yong Kwon, Joon-Suk Oh, Jung-Pyo Hong, Seung-Chul Hong, Youngkwan Lee, Hyouk Ryeo Choi, Kwang J. Kim, Mainul Hossain Bhuiya, Jae Do Nam Jan 2013

Transparent Actuator Made With Few Layer Graphene Electrode And Dielectric Elastomer, For Variable Focus Lens, Taeseon Hwang, Hyeok-Yong Kwon, Joon-Suk Oh, Jung-Pyo Hong, Seung-Chul Hong, Youngkwan Lee, Hyouk Ryeo Choi, Kwang J. Kim, Mainul Hossain Bhuiya, Jae Do Nam

Mechanical Engineering Faculty Publications

A transparent dielectric elastomer actuator driven by few-layer-graphene (FLG) electrode was experimentally investigated. The electrodes were made of graphene, which was dispersed inN-methyl-pyrrolidone. The transparent actuator was fabricated from developed FLG electrodes.The FLG electrode with its sheet resistance of 0.45 kΩ/sq (80 nm thick) was implemented to mask silicone elastomer. The developed FLG-driven actuator exhibited an optical transparency of over 57% at a wavenumber of 600 nm and produced bending displacement performance ranging from 29 to 946 μm as functions of frequency and voltage. The focus variation was clearly demonstrated under actuation to study ...


Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman Jan 2009

Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman

Birck and NCN Publications

Carbon nanotubes (CNTs) have gained increased interest in dynamic atomic force microscopy (dAFM) as sharp, flexible, conducting, nonreactive tips for high-resolution imaging, oxidation lithography, and electrostatic force microscopy. By means of theory and experiments we lay out a map of several distinct tapping mode AFM oscillation states for CNT tipped AFM cantilevers: namely, noncontact attractive regime oscillation, intermittent contact with CNT slipping or pinning, or permanent contact with the CNT in point or line contact with the surface while the cantilever oscillates with large amplitude. Each state represents fundamentally different origins of CNT-surface interactions, CNT tip-substrate dissipation, and phase contrast ...