RT journal article
T1 Quantitative, Spectro-kinetic Analysis of Oxygen in Electron-Beam Sensitive, Multimetallic Oxide Nanostructures
A1 López Haro, Miguel
A1 Gómez-Recio, Isabel
A1 Pan, Huiyan
A1 Delgado Jaén, Juan José
A1 Chen, Xiaowei
A1 Cauqui López, Miguel Ángel
A1 Pérez Omil, José Antonio
A1 Ruiz-González, María Luisa
A1 Hernando, María
A1 Parras, Marina
A1 González-Calbet, José M.
A1 Calvino Gámez, José Juan
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
K1 chrono-spectroscopy-electron tomographycombination
K1 electron-beam sensitive materials
K1 oxygen stoichiometry
K1 potassium-manganese hollandites
K1 quantitative XEDS at nanoscale
AB The oxygen stoichiometry of hollandite, KxMnO2-δ, nanorods has been accurately determined from a quantitative analysis of scanning-transmission electron microscopy (STEM) X-Ray Energy Dispersive Spectroscopy (XEDS) experiments carried out in chrono-spectroscopy mode. A methodology combining 3D reconstructions of high-angle annular dark field electron tomography experiments, using compressed-sensing algorithms, and quantification through the so-called ζ-factors method of XEDS spectra recorded on a high-sensitivity detector has been devised to determine the time evolution of the oxygen content of nanostructures of electron-beam sensitive oxides. Kinetic modeling of O-stoichiometry data provided K0.13MnO1.98 as overall composition for nanorods of the hollandite. The quantitative agreement, within a 1% mol error, observed with results obtained by macroscopic techniques (temperature-programmed reduction and neutron diffraction) validate the proposed methodology for the quantitative analysis, at the nanoscale, of light elements, as it is the case of oxygen, in the presence of heavy ones (K, Mn) in the highly compromised case of nanostructured materials which are prone to electron-beam reduction. Moreover, quantitative comparison of oxygen evolution data measured at macroscopic and nanoscopic levels allowed us to rationalize beam damage effects in structural terms and clarify the exact nature of the different steps involved in the reduction of these oxides with hydrogen.
PB Oxford University Press
SN 1435-8115
YR 2023
FD 2023
LK http://hdl.handle.net/10498/32577
UL http://hdl.handle.net/10498/32577
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 13-nov-2026