scispace - formally typeset
Search or ask a question
Topic

Chemical state

About: Chemical state is a research topic. Over the lifetime, 2378 publications have been published within this topic receiving 78183 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: To understand the effect of transition-metal-based additives added to reactive hydride composites, the chemical state and changes during the reaction as well as the microstructural distribution were investigated using x-ray absorption near-edge structure (XANES) spectroscopy and anomalous small-angle x-rays scattering (ASAXS).
Abstract: Reactive hydride composites (RHCs) are very promising hydrogen storage materials for future applications due to their reduced reaction enthalpies and high gravimetric capacities. At present, the materials' functionality is limited by the reaction kinetics. A significant positive influence can be observed with addition of transition-metal-based additives. To understand the effect of these additives, the chemical state and changes during the reaction as well as the microstructural distribution were investigated using x-ray absorption near-edge structure (XANES) spectroscopy and anomalous small-angle x-ray scattering (ASAXS). In this work, zirconium- and vanadium-based additives were added to 2LiBH4–MgH2 composites and 2LiH–MgB2 composites and measured in the vicinity of the corresponding absorption edge. The measurements reveal the formation of finely distributed zirconium diboride and vanadium-based nanoparticles. The potential mechanisms for the observed influence on the reaction kinetics are discussed.

55 citations

Journal ArticleDOI
TL;DR: The chemical state of oxygen on the surfaces of mixed electronic-ionic conducting La 0.6 Sr 0.4 Co 1− y Fe y O 3 ceramics was characterized by X-ray photoelectron spectroscopy (XPS).

55 citations

Journal ArticleDOI
TL;DR: In this paper, the results of a detailed study on the electrochemistry of an arsenopyrite mineral and a concentrate as well as other mineral species contained in it in a chloride medium (NaCl 1.9 M+HCl 0.1 M) using cyclic voltammetry were discussed.

55 citations

Journal ArticleDOI
TL;DR: A general phenomenon is pointed to whereby the growth scheme and the substrate-to-surface-Pt distance dictates the chemical state of the surface Pt atoms, and thereby, the performance of Pt-based surface-intensive devices.
Abstract: The surface atomic structure and chemical state of Pt is consequential in a variety of surface-intensive devices. Herein we present the direct interrelationship between the growth scheme of Pt films, the resulting atomic and electronic structure of Pt species, and the consequent activity for methanol electro-oxidation in Pt/TiO2 nanotube hybrid electrodes. X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) measurements were performed to relate the observed electrocatalytic activity to the oxidation state and the atomic structure of the deposited Pt species. The atomic structure as well as the oxidation state of the deposited Pt was found to depend on the pretreatment of the TiO2 nanotube surfaces with electrodeposited Cu. Pt growth through Cu replacement increases Pt dispersion, and a separation of surface Pt atoms beyond a threshold distance from the TiO2 substrate renders them metallic, rather than cationic. The increased dispersion and the metallic character of Pt results in...

55 citations


Network Information
Related Topics (5)
Oxide
213.4K papers, 3.6M citations
90% related
Thin film
275.5K papers, 4.5M citations
89% related
Carbon nanotube
109K papers, 3.6M citations
87% related
Raman spectroscopy
122.6K papers, 2.8M citations
87% related
Nanoparticle
85.9K papers, 2.6M citations
86% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202326
202249
202184
202089
201987
201894