Photoemission
Mostrando 1-12 de 23 artigos, teses e dissertações.
-
1. Bimetallic Au-Pd/α-MoO3 Catalyst with High Oxygen Vacancies for Selective Oxidation of Cinnamyl Alcohol
Supported Au-Pd nanoparticles (NPs) have been extensively studied in alcohol oxidation reactions. However, few studies use reducible metal oxides as support, which can activate oxygen molecules and boost the selectivity of the reaction. In this work, Au-Pd NPs were supported on α-MoO3 and evaluated in the selective oxidation of cinnamyl alcohol without solv
Journal of the Brazilian Chemical Society. Publicado em: 2023
-
2. Enhancement of Visible Light-Responsive Photocatalytic Efficiency by Using a Laccaic Acid-Modified Titanium Dioxide Photocatalyst
In this study, a laccaic acid-modified TiO2 photocatalyst (Lac-TiO2) was prepared via an impregnation method with 0.50, 1.00, 2.50, and 5.00 wt.% laccaic acid. The products’ physical properties were examined through X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoemission spectroscopy (XPS), UV-Vis diffused
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
3. Catalytic oxidation of volatile organic compounds (n-hexane, benzene, toluene, o-xylene) promoted by cobalt catalysts supported on γ-Al2O3-CeO2
Cobalt catalysts supported on γ-alumina, ceria and γ-alumina-ceria, with 10 or 20%wt of cobalt load, prepared by the wet impregnation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission transmission electron microscopy (FETEM), N2 adsorption-desorption isotherms (BET/BJH methods), energy-dispersive X-ray
Braz. J. Chem. Eng.. Publicado em: 2014-09
-
4. Aplicação de espectroscopia de fotoelétrons ao estudo de processos de corrosão e oxidação de superfícies metálicas: Inconel 182, Fe/Cu(100) e U-Zr-Nb / Aplicação de espectroscopia de fotoelétrons ao estudo de processos de corrosão e oxidação de superfícies metálicas: Inconel 182, Fe/Cu(100) e U-Zr-Nb
In this work a study of the oxidation/corrosion process of three systems of metallic materials by Photoemission Spectroscopy is presented. In the first system, it was investigated the corrosion of Inconel 182 at simulated Pressurized Water Reactor (PWR) environment. Samples with and without surface chemical treatment were exposed to the simulated environment
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/05/2011
-
5. Tuning luminescence of 3d transition- metal doped quantum particles: Ni+2: CdS and Fe+3: CdS
The room- temperature photoluminescence of Cd1- xMxS (M=Ni, Fe) nanoparticles were investigated. Compared with the photoluminescence of CdS which peaks at 475 nm, the photoemission of CdS:Fe nanoparticles was peaking at 537 nm because of Fe acting as luminescent centers. On the other hand, the green emission (503 nm) of CdS:Ni attributed to the ¹T2g(D)→ �
Brazilian Journal of Physics. Publicado em: 2010-09
-
6. Photoluminescence, photoabsorption and photoemission studies of hydrazone thin film used as hole transporting material in OLEDS
A fotoluminescência de filmes finos de 1-(3-metilfenil)-1,2,3,4-tetrahidroquinolina-6-carboxialdeído-1,1’-difenilhidrazona foi monitorada em função da irradiação com luz UV. A intensidade da emissão decresce exponencialmente com o tempo de exposição, sugerindo degradação das amostras. Com o objetivo de investigar os mecanismos de degradação e
Publicado em: 2010
-
7. Photoluminescence, photoabsorption and photoemission studies of hydrazone thin film used as hole transporting material in OLEDs
A fotoluminescência de filmes finos de 1-(3-metilfenil)-1,2,3,4-tetrahidroquinolina-6-carboxialdeído-1,1'-difenilhidrazona foi monitorada em função da irradiação com luz UV. A intensidade da emissão decresce exponencialmente com o tempo de exposição, sugerindo degradação das amostras. Com o objetivo de investigar os mecanismos de degradação e de
Journal of the Brazilian Chemical Society. Publicado em: 2008
-
8. Formação e reatividade de filmes finos de macrocíclicos de ferro sobre silício monocristalino / Formation and reactivity of iron macrocycle thin films on oxidized silicon wafer- SiO2/Si
This work describes the study of model surfaces on oxidized silicon wafer, SiO2/Si, modified with N-heterocycles rings, that allows the grafting of a macrocycle iron complex, FeTIM, that could be used in reactivity studies, with biologically relevant molecules, as nitrogen monoxide (NO). On this way, the synthesis of these silanes and a new methodology of th
Publicado em: 2007
-
9. Inverse photoemission spectroscopy of multiwall carbon nanotubes
Multiwall Carbon Nanotubes (MWCNTs) were synthesized by Chemical Vapor Deposition (CVD). Two different procedures were used to grow MWCNT films roughly, aligned in the direction normal to the SiO2/Si(111) substrate. Inverse Photoemission Spectroscopy measurements, on these samples, show the existence of resonances which could be traced back to a flat graphen
Brazilian Journal of Physics. Publicado em: 2006-09
-
10. Electron field emission measurements from boron-doped CVD diamond on tantalum
Boron-doped polycrystaline diamond films grown by hot-filament-assisted chemical vapor deposition were studied with ultraviolet photoemission spectroscopy (UPS), Raman spectroscopy, X-ray diffractometry and current voltage measurements. The UPS measurement shows that the work function (phi) without electric field is about 3.9 eV . The field-emission current-
Brazilian Journal of Physics. Publicado em: 2003-03
-
11. Estudo da estrutura eletronica de ligas NiCu por espectroscopia de eletrons excitados por raio-X
In this work we propose to study the electronic structure of Ni1-xC ux alloys with various concentration (0 £ x £ 1) using photoemission (XPS) and Auger electron spectroscopy (XAES).The main objective is to verify the charge transfer between the Cu and Ni atoms, when these elements form alloys. We measured and compared core level energies (2p3/2) of Cu and
Publicado em: 2002
-
12. Structure and property relationships of amorphous CNx: a joint experimental and theoretical study
Amorphous CNx and CNx:H have been prepared by the ion beam assisted deposition technique. Samples were characterized through X-ray and UV photoemission, IR absorption and Raman spectroscopies. These spectra have been interpreted with the aid of quantum chemical calculations based upon the Hartree-Fock theory on several molecular models. The understanding of
Brazilian Journal of Physics. Publicado em: 2000