scispace - formally typeset
Search or ask a question
Topic

Noble metal

About: Noble metal is a research topic. Over the lifetime, 15113 publications have been published within this topic receiving 337947 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, the chemical and mechanistic aspects of the selective catalytic reduction (SCR) of NO by ammonia and by methane have been investigated, and the classical NH 3 -SCR process, operating near 600k over vanadia-titania-based catalysts, is shown to imply the activation of NO x in the form of an adsorbed oxidized species, that reacts with the reductant, CH 4, from the gas phase or activation into the zeolite channels.

164 citations

Journal ArticleDOI
TL;DR: In this paper, the degradation of oxalic acid has been studied in aqueous solution photocatalyzed by band-gap-irradiated TiO2, modified with nanosized gold particles.
Abstract: The commercially available TiO2-photocatalyst (Degussa P25) was modified with nanosized gold particles by the photoreduction method at four different values of the pH factor of the medium. The characterization of the synthesized catalysts was carried out by the BET method, X-ray photoelectron spectroscopy (XPS), TEM and the adsorption of the model pollutant. A remarkable influence of the pH on the particle size of Au was registered upon investigating the catalysts by XPS and TEM methods. The size of the gold nanoparticles on the TiO2 surface decreases with increase in the pH of the medium. The degradation of oxalic acid has been studied in aqueous solution photocatalyzed by band-gap-irradiated TiO2, modified with nanosized gold particles. The photocatalytic activity of TiO2, modified with gold, was found to increase with the decrease of the size of the gold nanoparticles on the surface of the photocatalytic material. The maximal value of the photocatalytic activity (twice higher than that of the semiconducting support) is registered in the case of gold photoreduction at pH 7. The adsorption properties of the catalysts, as well as the size of the noble metal nanoparticles on the surface of the support, influence the efficiency of the photocatalytic process. The reaction rate of photocatalytic degradation of the oxalic acid follows a zero kinetic order according to the Langmuir–Hinshelwood model. The increase of the quantum yield of the photodestruction reaction of the studied model pollutant is due to the formation of Schotky barriers on the metal-semiconductor interface, which serve as efficient electron traps, preventing the electron–hole recombination.

164 citations

Journal ArticleDOI
TL;DR: The activity and selectivity of alumina-supported Pt, Pd, and Pt-Pd catalysts in the hydrodesulfurization of dibenzothiophene (DBT) and 4,6-dimethyldibenzethiophene(4,6)-DM-DBT were investigated, and all final, hydrocarbon products and partially hydrogenated intermediates were analyzed as discussed by the authors.

164 citations

Journal ArticleDOI
TL;DR: In this article, the block copolymer polystyrene-b-poly-4-vinylpyridine in toluene was analyzed by electron microscopy and various techniques of X-r...
Abstract: Monometallic and bimetallic colloids were prepared in micelles of the block copolymer polystyrene-b-poly-4-vinylpyridine in toluene and analyzed by electron microscopy and various techniques of X-r...

163 citations

Journal ArticleDOI
TL;DR: In this paper, a binary two dimensional (2D) hybrid of black phosphorus (BP) and WS2 as noble metal-free NIR-driven photocatalyst for H2 production was reported.
Abstract: Efficient production of H2 from water using solar energy holds tremendous promise for clean energy. The optimal photocatalysts require earth abundant elements for the cost-effective as well as harvesting broad spectrum of solar light, particularly in the near-infrared (NIR) region. Therefore, pathways leading to NIR-driven H2 production activity on noble metal-free photocatalyst are of high scientific and economic interest. Here we report a binary two dimensional (2D) hybrid of black phosphorus (BP) and WS2 as noble metal-free NIR-driven photocatalyst for H2 production. Under >780 nm NIR light irradiation, substantive H2 productions were observed. Compare to pure BP and WS2, the solid enhancement (21 and 50 folds) of photocatalytic activity was achieved in the BP/WS2 hybrid. The mechanism has been investigated by photoelectrochemical measurements, electron reductive reaction analyses, and transient absorption spectroscopy. It is indicated that 2D BP/WS2 hybrid has great potential as a noble metal-free NIR-driven photocatalyst for solar energy conversion.

163 citations


Network Information
Related Topics (5)
Oxide
213.4K papers, 3.6M citations
92% related
Nanoparticle
85.9K papers, 2.6M citations
92% related
Graphene
144.5K papers, 4.9M citations
91% related
Adsorption
226.4K papers, 5.9M citations
91% related
Carbon nanotube
109K papers, 3.6M citations
90% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023485
2022986
2021622
2020724
2019896
2018767