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Your search keyword '"Chakraborty, Parthojit"' showing total 103 results
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103 results on '"Chakraborty, Parthojit"'

11. A Neural Network-Based DPD Coefficient Determination for PA Linearization in 5G and Beyond-5G mmWave Systems

Author

Narayanan, Aravind Tharayil, primary, Minati, Ludovico, additional, Hagihara, Aran, additional, Kobayashi, Jun, additional, Shimura, Toshihiro, additional, Kawano, Yoichi, additional, Chakraborty, Parthojit, additional, Bartels, Jim, additional, Tokgöz, Korkut Kaan, additional, Dosho, Shiro, additional, Suzuki, Toshihide, additional, and Ito, Hiroyuki, additional

Published
2024
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15. New Trend of Amperometric Gas Sensors Using Atomic Gold-Decorated Platinum/Polyaniline Composites.

Author

Faricha, Anifatul, Chakraborty, Parthojit, Chang, Tso-Fu Mark, Sone, Masato, and Nakamoto, Takamichi

Subjects
AMPEROMETRIC sensors, GAS detectors, PLATINUM, SCIENTIFIC literature, GOLD nanoparticles, AQUEOUS electrolytes, IONIC liquids, QUARTZ crystal microbalances
Abstract

The Amperometric Gas Sensor (AGS) uses an electrode as the transducer element which converts its signal into a current from the electrochemical reaction of analytes taking place at the electrode surface. Many attempts to improve AGS performance, such as modifying the working electrode, applying a particular gas-permeable membrane, and selecting the proper electrolyte, etc., have been reported in the scientific literature. On the other hand, in the materials community, atomic gold has gained much attention because its physicochemical properties dramatically differ from those of gold nanoparticles. This paper provides an overview of the use of atomic gold in AGSs, both in a bulky AGS and a miniaturized AGS. In the miniaturized AGS, the system must be redesigned; for example, the aqueous electrolyte commonly used in a bulky AGS cannot be used due to volatility and fluidity issues. A Room Temperature Ionic Liquid (RTIL) can be used to replace the aqueous electrolyte since it has negligible vapor pressure; thus, a thin film of RTIL can be realized in a miniaturized AGS. In this paper, we also explain the possibility of using RTIL for a miniaturized AGS by incorporating a quartz crystal microbalance sensor. Several RTILs coated onto modified electrodes used for isomeric gas measurement are presented. Based on the results, the bulky and miniaturized AGS with atomic gold exhibited a higher sensor response than the AGS without atomic gold. [ABSTRACT FROM AUTHOR]

Published
2024
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23. Array of Miniaturized Amperometric Gas Sensors Using Atomic Gold Decorated Pt/PANI Electrodes in Room Temperature Ionic Liquid Films

Author

Anifatul, Faricha, Yoshida, Shohei, CHAKRABORTY, P, CHAKRABORTY, Parthojit, Okamoto, Keisuke, Chang, Tso-Fu Mark, Sone, Masato, and NAKAMOTO, TAKAMICHI

Subjects
atomic gold decorated Pt/PANI electrodes, butanol isomers gas measurement, catalytic activity, miniaturized electrochemical sensors, room temperature ionic liquid, Electrical and Electronic Engineering, Biochemistry, Instrumentation, Atomic and Molecular Physics, and Optics, Analytical Chemistry
Abstract

Miniaturized sensors possess many advantages, such as rapid response, easy chip integration, a possible lower concentration of target compound detection, etc. However, a major issue reported is a low signal response. In this study, a catalyst, the atomic gold clusters of Aun where n = 2, was decorated at a platinum/polyaniline (Pt/PANI) working electrode to enhance the sensitivity of butanol isomers gas measurement. Isomer quantification is challenging because this compound has the same chemical formula and molar mass. Furthermore, to create a tiny sensor, a microliter of room-temperature ionic liquid was used as an electrolyte. The combination of the Au2 clusters decorated Pt/PANI and room temperature ionic liquid with several fixed electrochemical potentials was explored to obtain a high solubility of each analyte. According to the results, the presence of Au2 clusters increased the current density due to electrocatalytic activity compared to the electrode without Au2 clusters. In addition, the Au2 clusters on the modified electrode had a more linear concentration dependency trend than the modified electrode without atomic gold clusters. Finally, the separation among butanol isomers was enhanced using different combination of room-temperature ionic liquids and fixed potentials.

Published
2023
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39. Catalytic Activity of Atomic Gold-Decorated Polyaniline Support in Glucose Oxidation

Author

Ito, Yuki, Chang, Tso-Fu Mark, CHIEN, Yu-An, Chien, Yu-An, Chen, Chun Yi, CHAKRABORTY, P, CHAKRABORTY, Parthojit, NAKAMOTO, TAKAMICHI, and Sone, Masato

Subjects
Working electrode, Chemistry, 020209 energy, 010401 analytical chemistry, 02 engineering and technology, 01 natural sciences, 0104 chemical sciences, Electrochemical gas sensor, Catalysis, chemistry.chemical_compound, Atomic radius, Electrode, Polyaniline, 0202 electrical engineering, electronic engineering, information engineering, Cyclic voltammetry, Nuclear chemistry
Abstract

Atomic-level gold clusters are decorated on a polyaniline (PANI) support by a cyclic atomic electrodeposition process, and the catalytic activity in the oxidation of glucose is studied. The evaluation is conducted by cyclic voltammetry using atomic-level gold clusters-decorated PANI (PANI/AuN, where N indicates the atomic size of the Au cluster and N = 1~3 in this study) as the working electrode and a solution containing 0 to 50.0 mM of glucose in phosphate-buffered saline. The catalytic activity is determined from the oxidation current observed at around +0.6 V vs. Ag/AgCl. The catalytic activity is found to be affected by the size of gold clusters decorated on the PANI/AuN, whereby the catalytic activity is low when N is 1 or 3. On the other hand, an obvious enhancement in the catalytic activity is observed for the PANI/Au2 electrode.

Published
2020

41. Design and development of amperometric gas sensor with atomic Au–Polyaniline/Pt composite

Author

CHAKRABORTY, P, CHAKRABORTY, Parthojit, CHIEN, Yu-An, Chien, Yu-An, Chiu, Wan-Ting, Chang, Tso-Fu Mark, Sone, Masato, NAKAMOTO, TAKAMICHI, and Janata, Jiri

Subjects
Conductive polymer, Materials science, Composite number, Amperometry, Catalysis, Reaction rate, chemistry.chemical_compound, Atomic layer deposition, chemistry, Chemical engineering, Polyaniline, Electrode, Electrical and Electronic Engineering, Instrumentation
Abstract

Rapid advancements in information processing and embedded systems require high selective and fast sensors. Conventional gas sensors are not suitable for the detection of isomers of organic compounds due to cross-sensitivity and the response time being limited by slow chemical kinetics. Amperometric gas sensors using conducting polymers modified with metal catalysts are a suitable and robust system due to many tunable properties. In this paper, conducting polymer polyaniline was electrochemically decorated with clusters containing precisely defined number of gold atoms to function as an electro-catalyst. The modified polymer composite showed fast reaction rate for the electro-oxidation of alcohols in both liquid and gas phases. The number of gold atoms affected the catalytic activity. Cyclic voltammograms were measured and results showed discriminable patterns between n-propanol and iso-propanol even at different gas concentrations. Thus, it was demonstrated that gas sensor arrays can be realized by decorating different number of gold atoms on polyaniline electrodes, to yield defined and different selectivity.

Published
2020

50. Indirect Sensing of Lower Aliphatic Ester Using Atomic Gold Decorated Polyaniline Electrode

Author

CHAKRABORTY, P, CHAKRABORTY, Parthojit, CHIEN, Yu-An, Chien, Yu-An, Chang, Tso-Fu Mark, Sone, Masato, and NAKAMOTO, TAKAMICHI

Subjects
ethyl formate, principal component analysis, 020209 energy, bi-atomic gold, Inorganic chemistry, 02 engineering and technology, lcsh:Chemical technology, amperometric gas sensor, 01 natural sciences, Biochemistry, Ethyl formate, Article, polyaniline, Analytical Chemistry, chemistry.chemical_compound, Hydrolysis, Polyaniline, 0202 electrical engineering, electronic engineering, information engineering, lcsh:TP1-1185, Electrical and Electronic Engineering, Instrumentation, Conductive polymer, Ethanol, Nanocomposite, Chemistry, 010401 analytical chemistry, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Electrode
Abstract

Novel sensing materials have been formed by decorating polyaniline conducting polymers with atomic gold clusters where the number of atoms is precisely defined. Such materials exhibit unique electrocatalytic properties of electrooxidation to aliphatic alcohols, although analytes with other functional groups have not been studied. This paper reports a study of cyclic voltammetric patterns obtained with bi-atomic gold nanocomposite response to analytes with other functional groups for sensor applications. Principal component analysis shows separation among normal-propanol, iso-propanol and ethyl formate/ethanol groups. Indirect sensing of ethyl formate is demonstrated by electrooxidation of the product upon hydrolysis in alkaline medium. Voltammograms of ethyl formate are studied in gaseous phases.

Published
2020

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