Abstracts Book - IMRC 2018

• SE2-O029
ROTARY-HYDROTHERMAL METHOD TO PRODUCE BaCuSi2O6
POWDERS: EFFECT OF THE COOPER PRECURSOR
Diego Antonio Corona Martínez 1 , Juan Carlos Rendón Angeles 1 , Jorge López Cuevas 1 , Kazumichi
Yanagisawa 2
1 Centro de Investigación y de Estudios Avanzados del IPN - CINVESTAV Unidad Saltillo, Ceramic
engineering department, Mexico. 2 Kochi University, Research Laboratory of Hydrothermal
Chemistry, Faculty of Science, Japan.
The crystallization of BaCuSi 2 O 6 single-phase particles with different
morphologies was investigated under hydrothermal conditions. The synthesis
of the BaCuSi 2 O 6 powders occurred rapidly using the rotatory hydrothermal
process at a speed of 50 rpm. The experiments were conducted at various
temperatures (200–240 °C), for different reaction intervals, (3–24 h) using two
different fluids (water and NaOH solutions). Two chemical reagent precursors,
Cu(NO 3 ) 2 and CuCl 2 ; of Cu 2+ ions were selected for the hydrothermal treatments.
These reaction products were characterized by XRD, FT-IR, FE-SEM and the
chemical composition of the powders was measured by ICP-AES. In addition, the
results showed differences in the lattice parameters calculated by Rietveld
refinement. The crystallization of the BaCuSi 2 O 6 powders only occurred at 240
°C, using only water as solvent, for a reaction interval as short as 6 h. However,
at intermediate intervals above 12 h, the obtained particles in each Cu 2+
precursor had different morphologies. The results shown that a preferential
formation of agglomerated particles resembling a nest-like shape with an
average size of 2.5 µm, occurred when Cu(NO 3 ) 2 was used. In contrast, the
particles produced using CuCl 2 exhibited an ellipsoidal agglomerated
morphology with a size of ~2 µm. The particle formation was promoted by the
dissolution-precipitation mechanism of a precursor colloidal-gel, while the
crystal growth was enhanced by the dissolution-recrystallization mechanism of
the intermediate synthesized crystalline phases including the BaCuSi 2 O 6 , which
occurred in the hydrothermal media. In both cases, the size distribution and the
morphology of the obtained powders were homogeneous, obtaining pigments
with a slight hue difference in the purple colour. The pigment obtained using
Cu(NO 3 ) 2 had L/a/bcolour coordinates of 63.071/18.849/-22.720; and the same
powder fabricated using CuCl 2 exhibits the parameters 57.348/3.976/-17.021.
Acknowledgment: