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Effective hydrogen gas sensor based on palladium nanoparticles dispersed on graphene sheets by spin coating technique

Inpaeng Saowaluk, Muangrat Worawut, Tedsree Karaked, Pfeiler Wolfgang, Chodjarusawad Thanawee, Issro Chaisak

Materials Science Poland

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2020

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Vol. 38, No. 2

305--311

EN

A room-temperature hydrogen gas (H2) sensor was successfully fabricated by dispersion of palladium nanoparticles (Pd NPs) on graphene sheets (GRs) (hereafter referred to as “Pd NPs/GRs”). GRs and Pd NPs were synthesized by chemical vapor deposition technique and by polyol process, respectively. A colloidal solution of Pd NPs with an average diameter of 11 nm was then dispersed onto the GRs by spin coating technique. The density of dispersed Pd NPs on GRs was controlled by varying the volume of the dispersed solution within the range of 50 – 150 μL. The fabricated Pd NPs/GRs sensors exhibited a high sensitivity for H2 gas with a concentration of 1500 – 6000 ppm at room temperature. Upon H2 exposure, the Pd NPs/GRs sensors showed an increase in electrical resistance, which could easily be measured. The relationship between sensor response and H2 concentration is in correspondence with the Langmuir adsorption model. The H2 detection limit is estimated to be 1 ppm. The results demonstrate that the Pd NPs/GRs sensor is an easily fabricated, but very effective means for room-temperature detection of H2 at ppm level.

2

Reduced graphene oxide and inorganic nanoparticles composites – synthesis and characterization

Onyszko M., Urbaś K., Aleksandrzak M., Mijowska E.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 4

95--103

EN

Graphene – novel 2D material, which possesses variety of fascinating properties, can be considered as a convenient support material for the nanoparticles. In this work various methods of synthesis of reduced graphene oxide with metal or metal oxide nanoparticles will be presented. The hydrothermal approach for deposition of platinum, palladium and zirconium dioxide nanoparticles in ethylene glycol/water solution was applied. Here, platinum/reduced graphene oxide (Pt/RGO), palladium/reduced graphene oxide (Pd/RGO) and zirconium dioxide/reduced graphene oxide (ZrO2/RGO) nanocomposites were prepared. Additionally, manganese dioxide/reduced graphene oxide nanocomposite (MnO2/RGO) was synthesized in an oleic-water interface. The obtained nanocomposites were investigated by transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), Raman spectroscopy and thermogravimetric analysis (TGA). The results shows that GO can be successfully used as a template for direct synthesis of metal or metal oxide nanoparticles on its surface with a homogenous distribution.

3

Obtaining and description of the MWCNTs-Pd nanocomposite

Dobrzańska-Danikiewicz A. D., Cichocki D., Łukowiec D.

Archives of Materials Science and Engineering

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2015

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Vol. 74, nr 1

15--22

EN

Purpose: The main aim of the research was to produce nanocomposites consisting of carbon nanotubes coated with palladium nanoparticles and the characterisation of the obtained materials. Design/methodology/approach: High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100-400 nm and the diameter of 6-25 nm obtained in advance with Catalytic Chemical Vapour Deposition (CCVD) were employed in the investigations. Carbon nanotubes–palladium nanoparticles system was fabricated by direct deposition of palladium nanoparticles, produced earlier, onto the surface of multiwall carbon nanotubes. Findings: The investigations using transmission electron microscopy together with an EDS and XPS analysis have confirmed the fact of producing an MWCNTs-Pd nanocomposite. Examinations with Raman spectroscopy have allowed to determine the difference between the degree of defects of carbon nanotubes before and after modification with palladium nanoparticles. Research limitations/implications: The presence of palladium has influence on the electrical properties of the nanocomposite, enhances sensitivity and selectivity of the CNTsNPs system in contact with the chosen chemical substance, and the result is the changing of the conductivity of nanotubes. It is a basis for the application of the studied material as an active substance of sensors of chemical/biological compounds. Originality/value: The paper presents the results of investigations relating to the synthesis of a nanocomposite material consisting of multiwalled carbon nanotubes and Pd nanoparticles and the characteristics of the material produced in terms of its structure, morphology and the distribution of Pd nanoparticles on the external surface of multiwalled carbon nanotubes and chemical composition.

4

Badanie nanokompozytów węglowo-palladowych metodami TEM i CL

Sobczak K., Witkowski B. S., Dłużewski R., Kowalska E., Kozłowski M., Czerwosz E.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 8

87-89

PL

W artykule zaprezentowano wyniki badań przeprowadzonych na nanoporowatych materiałach węglowo-palladowych otrzymanych w procesie CVD (Chemical Vapor Deposition). Badania te zostały wykonane za pomocą transmisyjnego mikroskopu elektronowego (TEM) oraz skaningowego mikroskopu elektronowego (SEM), wyposażonego w system katodolumi-nescencji (CL). Kompozyty węglowo-palladowe znajdą zastosowanie jako warstwa aktywna w detektorach wodoru, oraz jego związków. Przeprowadzone badania wykazały, iż niektóre nanocząstki palladu posiadają otoczkę z grafitu i są aktywne optycznie.

EN

In this paper we presented results of investigation of carbonaceous-palladium materials obtained in the CVD (Chemical Vapor Deposition) process. This investigations were carried out with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), equipped with speetrum imaging for cathodoluminescence (CL). The composites will be applied as a active layers in hydrogen and also hydrocarbons detectors. Our measurements showed that some of Pd nanoparticles have a graphite shell and also are optically active.