Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 23 for “"Platinum Nanoparticles"”.
-
Platinum Nanoparticles to Study Metal Location in Shape-Selective Hydrocracking
In the petrochemical industry, bifunctional hydrocracking is used to further refine long chain hydrocarbon product molecules into smaller, more valuable fragments (such as diesel and aviation fuel). The current study is focused on using hydrocracking to increase diesel yield, as the preferred …
-
Oxygen reduction reaction on carbon supported dispersed platinum nanoparticles and extended platinum surfaces
To date, the cost of high platinum loadings in polymer electrolyte fuel cells (PEFCs) remains one of the main deterrents preventing their broad commercialisation. The reaction of interest in this work is the oxygen reduction reaction (ORR) occurring at the cathode side of the PEFC. The ORR has been …
-
Model studies on photocatalysis: laser induced CO desorption from platinum nanoparticles at an alumina support
Es wurde die Adsorption von CO Molekülen bei 90 K auf verschiedenen Pt Nanopartikeln untersucht, welche durch PVD bei 300 K auf eptiaktischen Al2O3 Filmen abgeschieden wurden. Die Filme wurden durch oberflächliche Oxidierung eines NiAl(110) Kristalls präpariert. Durch Anregung mittels eines …
-
Electrochemical investigation of platinum nanoparticles supported on carbon nanotubes as cathode electrocatalysts for direct methanol fuel cell
… no further investigation was done on them. The platinum wt% on the supports observed from EDS was 21.8, 19.10 and 16.74wt% for Pt/EMWCNT, Pt/LPGCNT and Pt/ commercial CNT respectively. Pt/LPGMWCNT showed high electro-catalytic activity of 2.48 mA and active surface area of 76 m2/g, toward oxygen …
-
Relation between surface structural and chemical properties of platinum nanoparticles and their catalytic activity in the decomposition of hydrogen peroxide
… of H₂O₂ to H₂O and molecular O₂ catalyzed by platinum nanocatalysts is technologically very important in several energy conversion technologies, such as steam propellant thrust applications and hydrogen fuel cells. However, the mechanism of H₂O₂ decomposition on platinum has been unresolved …
-
Novel chiral liquid crystal organic-inorganic hybrid nanoparticle systems : Design, synthesis and investigation
… were chemically attached to gold and iron/platinum nanoparticles. For all end materials exhaustive characterisation methods were applied.The questions that were tried to be answered were related to the attachment of cholesterol based mesogens to silsesquioxane cores. Furthermore, the …
-
Structure and Dynamics in Ligand-Protected and Supported Metal Nanoparticles
… measurements characterize metal clusters and nanoparticles on the basis of the number of metal atoms they contain. Ligand-protected 13-atom gold clusters serve as a model system to illustrate the capabilities of a correlated use of these techniques. They exhibit a molecular density of …
-
Atomistic simulations of semiconductor and metallic nanoparticles
Semiconductor and metallic nanoparticles have recently become an attractive area of intensive research due to their unique and diverse properties, that differ significantly from bulk materials. With a wide range of applications and potential uses in nanoelectronics, catalysis, medicine, chemistry …
-
Investigation of the potential catalytic activities of several metal organic framework (MOF) materials
… MOFs are used as catalyst supports for iron or platinum nanoparticles. The catalysts are prepared using incipient wetness impregnation method and characterized with Brunauer-Emmett-Teller (BET), pulse chemisorption, X-ray diffraction (XRD), temperature-programmed reduction (TPR), and …
-
Development of Tin Oxide As An Oxidation-Resistant Support For Pem Fuel Cells
… of the electrochemical surface area against platinum dissolution, agglomeration, and poisoning, and a negligible peroxide/water production ratio.</p> <p>In this study, a novel mesoporous SnO2 support was successfully prepared to take the place of conventional carbon supports because of its …
-
Nanoscale Manipulation of Pristine and Functionalized Freestanding Graphene Using Scanning Tunneling Microscopy
… freestanding graphene sheets functionalized with platinum nanoparticles. It is shown that the platinum particles are self-organized but are not encapsulated by the graphene. Instead the nanoparticles are anchored to the sheet by a small number of covalent bonds. In the future the techniques shown …
-
Effects of Electrode Surface Morphology on the Transduction of Ionic Polymer-Metal Composites
… conditions leads to the formation and growth of platinum nanoparticles with sharp tips and edges - called Pt nanothorn assemblies - at the polymer-electrode interface. IPMCs designed with such nanostructured Pt electrodes are first to be reported. The experiments demonstrate that the formation …
-
Electrodeposited nanoparticles: properties and photocatalytic applications
… oxygen reduction reaction (ORR) at (DNA linked) platinum nanoparticles. The ORR can be replaced with other reduction reactions to detect other species such as anthraquinones. The possibility of using this device for quantitative sensing of both DNA and other species is discussed.
-
Interfacial Electrochemistry and Surface Characterization: Hydrogen Terminated Silicon, Electrolessly Deposited Palladium & Platinum on Pyrolyzed Photoresist Films and Electrodeposited Copper on Iridium
… that the electroless deposition of palladium and platinum may be accomplished in hydrofluoric acid solutions to attain palladium and platinum nanoparticles on a this film carbon surface for use as an electrode. Catalysis of these substrates is studied using hydrogen evolution in acidic media, …
-
Ionic self-assembly of porphyrin micro-nano structures for solar hydrogen evolution
… to photocatalytically reduce aqueous gold(I) and platinum(IV) complexes to initiate and form nanostructures decorated with metal nanostructures on their surfaces. Photocatalytic reduction of both gold(I) thiosulfate and thiourea complexes lead to the metal-clover porphyrin nanocomposites. The …
-
Synthesis and Characterization of Platinum-Based Fuel Cell Catalysts
… obtained by spontaneous deposition of Ru onto platinum nanoparticles. Their reactivity toward methanol oxidation maximized at ruthenium packing density 0.4--0.5, displaying twice the activity of the commercial Pt-Ru alloy catalyst. COs adsorbed on these Pt/Ru nanoparticle consisted of two …
-
The development of targeting nanosystems for the treatment of glioblastoma and neuroblastoma tumours
… and therapeutic applications. Bimetallic gold-platinum nanoparticles (AuPtNPs) have recently attracted great attention for anti-cancer and catalysis applications due to the synergistic effects of combined metal atoms which enhance NP properties when compared to their monometallic NP …
-
Amphiphilic Diblock Copolymers: Study of Interpolyelectrolyte Complexation in Organic Media and Nanoencapsulation of Melatonin
… efficiencies were determined assaying the nanoparticles by HPLC and values of ca. 30-35% are shown by the nanocapsules. DLS measurements further confirmed well-defined unimodal particle size distributions for all formulations. It was also possible to successfully incorporate platinum …
-
Molecular simulation method development and implementation for fuel cell catalyst layers
… cell component is, together with high price of platinum as the catalyst, the main bottleneck inhibiting large- scale deployment of fuel cell electric vehicles and competition with internal combustion engines. There has been an ongoing debate in the literature about the resistance in the catalyst …
Page 1 of 2