Richa Baronia; Jyoti Goel; Sunil K. Singhal
Abstract
In the fabrication of direct methanol fuel cells (DMFCs) having high performance the essential conditions are (i) the design and construction of a suitable anode electrocatalyst comprising of Pt or a Pt based alloy nanoparticles methanol oxidation reaction (MOR) efficiently and effectively (ii) nature ...
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In the fabrication of direct methanol fuel cells (DMFCs) having high performance the essential conditions are (i) the design and construction of a suitable anode electrocatalyst comprising of Pt or a Pt based alloy nanoparticles methanol oxidation reaction (MOR) efficiently and effectively (ii) nature of support materials onto which these nanoparticles are anchored. In MOR one of the major problems is the adsorption of poisoneous carbonmoxide and other similar intermediates near the active surface of Pt active leading to its deactivation and also the crossover of methanol solution towards the cathodic side. All these factors, therefore, lower the overall electrochemical performance of the electro-catalysts. In the present review paper we report some of our important results of the synthesis of different Pt and Pt based anode electro-catalysts (Pt, PtCo alloys, PtCu alloys) anchored on different support materials such as reduced graphene oxide (rGO), Nitrogen doped rGO and a hybrid of rGO/CNTs for MOR and compared with few of those already reported recently. A detailed characterization of raw materials and the electro-catalysts synthesized in this work is also discussed using XRD, FT-IR, SEM, TEM etc. The electrochemical measurements were made using cyclic voltammetry in acidic medium at room temperature.
T. K. Maiti; M. Miura-Mattausch;H. J. Mattausch; Y. Ochi; D. Navarro
Abstract
In this letter, we focus on the robot movement on non-smooth ground-surface, detected by pressure sensor. A simulation tool has been developed to study the robot motion according to the ground-surface condition change. The effect of the robot-foot contact with the ground-surface is considered by elastic ...
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In this letter, we focus on the robot movement on non-smooth ground-surface, detected by pressure sensor. A simulation tool has been developed to study the robot motion according to the ground-surface condition change. The effect of the robot-foot contact with the ground-surface is considered by elastic properties to the ground. We performed simulation analyses for various surface conditions to control the robot dynamics with respect to pressure sensing data that incorporates the two-way interactions between robot and ground. We upgraded the robot by implementing the pressure sensors under its foot, to measure the real-time contact force between foot and ground-surface. The obtained sensing data is used to analyse the surface condition, for controlling robot-leg movement horizontally along the ground-surface. Consequently, the analysis results guide us to improve the motion of a real self-controlled walking robot.
Sharmistha Ghosh
Abstract
Antiferroelectric liquid crystals are considered as smarter materials for display technologies owing to their faster response time over conventional nematics. However there is large scope for modifications of its physical properties. In the present study multi-walled carbon nanotubes (MWCNT) are dispersed ...
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Antiferroelectric liquid crystals are considered as smarter materials for display technologies owing to their faster response time over conventional nematics. However there is large scope for modifications of its physical properties. In the present study multi-walled carbon nanotubes (MWCNT) are dispersed in a high tilted antiferroelectric liquid crystal composed of rod like molecules. The effects of nano-dispersion on electro-optical and dielectric properties of the host are studied in details. The time for switching between dark and bright states and the rotational viscosity are reduced and spontaneous polarization is enhanced considerably by minute addition of MWCNTs. The high tilt angle of the molecules necessary for obtaining good dark state in displays has not changed after dispersion of nanotubes. The strong interaction of the aromatic cores of the rod like liquid crystal molecules with the honey-comb pattern of the CNT walls is considered responsible behind such improvements of physical properties of the host.
Ina Schubert; Wilfried Sigle; Loic Burr; Peter A. van Aken; Christina Trautmann; Maria Eugenia Toimil-Molares
Abstract
Gold nanowires are attracting great attention due to their ability to sustain surface plasmons and are thus promising candidates for sensing applications such as surface enhanced Raman and infrared spectroscopy. Controlling all nanowire parameters is crucial to adjust the resonance wavelengths and to ...
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Gold nanowires are attracting great attention due to their ability to sustain surface plasmons and are thus promising candidates for sensing applications such as surface enhanced Raman and infrared spectroscopy. Controlling all nanowire parameters is crucial to adjust the resonance wavelengths and to obtain high electric field enhancements. We have fabricated Au nanowires with controlled dimensions and surface morphology by electro-deposition of Au and Au-Ag nanowires in the pores of ion-track-etched polymer templates. Smooth and rough nanowires are fabricated by the use of different polymer types. By dealloying of Au-Ag wires, porous Au wires are being created. In addition, we have analyzed the surface plasmonic properties of smooth and porous Au nanowires by scanning transmission electron microscopy combined with electron energy-loss spectroscopy. Our results reveal the excitation of five different longitudinal modes in the smooth as well as in the porous Au wire. The resonance energies of the porous wire are red-shifted compared to the energies of a smooth Au wire with same dimensions, which demonstrates that the surface morphology of the nanowire is an important parameter to tune the multipole surface plasmon modes to specific energies. Knowledge on the plasmonic properties of nanowires dependent on their surface morphology is indispensable for their efficient application for sensor technology.
Yoshiaki Hirano; Katsutoshi Ooe; Kazuyoshi Tsuchiya; Tomohiro Hosokawa; Kazuto Koike; Shigehiko Sasa
Abstract
A health monitoring system (HMS) involving a blood extraction device with a new type of hybrid biosensor comprising an enzyme and a semiconductor has recently been developed. A MOSFET was used as the transducer. The gate electrode was extracted from the MOSFET using a cable. Gold (Au)-plate-immobilized ...
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A health monitoring system (HMS) involving a blood extraction device with a new type of hybrid biosensor comprising an enzyme and a semiconductor has recently been developed. A MOSFET was used as the transducer. The gate electrode was extracted from the MOSFET using a cable. Gold (Au)-plate-immobilized glucose oxidase (Go) was used as a biosensor and attached to the gate electrode. Go was immobilized on a self-assembled spacer combined with an Au electrode by the cross-link method using BSA as an additional bonding material. The electrode could be used to detect electrons generated by the oxidization of hydrogen peroxide produced by the reaction between Go and glucose using the constant electric current measurement system of the MOSFET-type hybrid biosensor. The sensitivities for the diluted whole blood and blood plasma were 61.4 and 171.2 V/(mol/L), respectively. The hybrid biosensor was useful for HMS.
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