Synthesis and structural characterization of YVO3 prepared by sol–gel acrylamide polymerization and solid state reaction methods

Structural and morphology comparison between m-LaVO4 and LaVO3 compounds prepared by sol–gel acrylamide polymerization and solid state reaction

“…In the xerogel DTA it was suppress the strong endothermic and exothermic peaks at lower temperatures due to released of gases such as NO x , H 2 O and CO 2 from gel. Compared with conventional oven (12 h at 100 • C as we report in a previous work [49]), the use of microwaves has the advantage of very short reaction favours the phase formation taking place at much lower temperatures. Unfortunately the exact nature of the interaction of the microwaves with the reactants during synthesis of materials is somewhat unclear and speculative [70].…”

“…This synthesis method is fast, clean and easy to reproduce with the advantage of a reduction in the temperature to complete the chemical reaction [44][45][46][47][48]. Recently, this method was used to control the grain size homogeneity [49] and which also improve thermoelectric properties of samples [50].…”

X-ray absorption to determine the metal oxidation state of transition metal compounds

“…The resulting powders were characterized by x-ray difraction, and their size and morphology were studied by TEM and SEM. The only significative difference between the two samples was that the one prepared by sol-gel reaction presented a more homogeneous distribution of smaller crystals compared with the solid-state sample [10].…”

“…X-Ray diffraction (XRD) and x ray photoelectron spectroscopy (XPS) confirm the formation of the La 1−x Sr x CoO 3 structure with inhomogeneous grain size.The morphology and crystal size of the final samples were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). YVO 3 samples were obtained by reduction of YVO 4 prepared by two different methods: solid state reaction and sol-gel acrylamide polymerization [10]. Reduction was achieved by heating the YVO 4 samples to 850 • C under vacuum, in the presence of a metallic Zr rod.…”

“…The difference was in the production of the parent YVO 4 vanadate that was later reduced. The production routes of the parent vanadate were solid state reaction and sol-gel acrylamide polymerization [10]. X-Ray powder diffraction results indicate that the phases of both samples are identical, and that the main difference is in the crystal size.…”