Authors: Guerrero-Perez, MO; Lapina, OB; Rasmussen, SB; Banares, MA
Article; Early Access.
Top. Catal.. vol: . page: 1022-5528.
Date: 2023 MAY 29. 2023.
Doi: 10.1007/s11244-023-01827-2.
Abstract:
Nanoscaled-VPO (vanadium phosphate oxide) catalysts have been prepared on an alumina support with the objective of obtaining crystallites of the active phase with a high surface-to-volume ratio. Since the catalysed reaction occurs at the surface, these nanoscaled catalysts allows studying surface species transformations with a minimized signal from the bulk dominion. The chemical environment and oxidation state of these species has been determined by a combination of NMR, ESR and XANES spectroscopies. The results have allowed to optimize V + P coverage and V/P molar ratio to minimize the concentration of isolated vanadium oxide species and maximize V4+ concentration. The distribution of phosphorus islands ordered and significantly distorted of tetra- and penta-coordinated aluminium sites of the catalytic support, thus shaping the catalytic material to an optimal structure for the desired partial oxidation reaction..