title: A convenient and quantitative route to Sn(IV)-M [M = Ti(IV), Nb(V), Ta(V)] heterobimetallic precursors for dense mixed-metal oxide ceramics.
abstract: The strategy of reacting SnCl4 with M(OR)x provided a convenient and quantitative approach to new heterobimetallics with a simple addition formula, [SnCl4M(OR)x(HOR)y] (M = Ti, Nb, Ta; R = Et, Pr(i), x = 4, 5; y = 0-2) or sometimes an oxo complex [SnCl3(O)Ti2(OPr(i))7(HOPr(i))2]. The alcoholysis reactions of these heterometallics afforded mixed alkoxo complexes [SnCl4(μ-OEt)2M(Pr(i)O)x(Pr(i)OH)y] [M = Ti (x = y = 2), Nb, Ta (x = 3, y = 1)] under mild conditions, or a planar rectangular oxo product [SnCl3(μ-OEt)2Nb(OEt)2(EtOH)(μ-O)]2 at refluxing/extended stirring time. DFT calculations shed light on the stability and reactivity of these complexes. The use of these thoroughly characterized heterometallics as sol-gel precursors suppresses the formation of the undesired SnO2 grains, which are difficult to be sintered to a high density. The combined approach of using bottom-up synthesis of mixed Ti0.5Sn0.5O2 nanoparticles and Spark Plasma Sintering allowed the successful densification of chloride-free mixed-metal oxide ceramics. The influence of thermal treatment before sintering on the density and spinodal decomposition of the TiO2-SnO2 pellets is reported.
authors.affiliation: Université Lyon1, IRCELYON, 2 Avenue A. Einstein, 69626 Villeurbanne, France. shashank.mishra@ircelyon.univ-lyon1.fr.
authors.forename: Shashank
authors.initials: S
authors.lastname: Mishra
authors.forename: Erwann
authors.initials: E
authors.lastname: Jeanneau
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mangematin
authors.forename: Henry
authors.initials: H
authors.lastname: Chermette
authors.forename: Mahboubeh
authors.initials: M
authors.lastname: Poor Kalhor
authors.forename: Guillaume
authors.initials: G
authors.lastname: Bonnefont
authors.forename: Gilbert
authors.initials: G
authors.lastname: Fantozzi
authors.forename: Sylvie
authors.initials: S
authors.lastname: Le Floch
authors.forename: Stéphane
authors.initials: S
authors.lastname: Pailhes
authors.forename: Stéphane
authors.initials: S
authors.lastname: Daniele