Effect of magnesium source on the fabrication of kotoite Mg₃B₂O₆ ceramic

Abstract

The effect of magnesium source on the fabrication of kotoite, Mg3B2O6, ceramic has been investigated by high temperature solid‐state reaction route based on the calcination of different magnesium sources, containing magnesium oxide, magnesium carbonate, magnesium sulfate, and magnesium nitrate with boric acid. The X‐ray powder diffraction results showed that single‐phase kotoite, Mg3B2O6, was synthesized using MgNO3.6H2O and 5 wt.% excess of H3BO3 powders as starting materials at 900°C for 48 hours. Mg3B2O6 obtained, is well crystallized, in orhorhombic crystal structure with lattice parameters of a = 5.399(9), b = 8.424(6), and c = 4.506(5) Å. Jana2006 refinement of this product shows excellent fit of the experimental data with software data, GOF= 1.33. The crystallite size of the product was calculated as 40.50 nm using Debye‐Scherrer's equation. The existence of BO3 triangles were detected by FTIR measurements of Mg3B2O6. The thermal properties were studied in the temperature range of 20°C to 1400°C by TG/DTA. The results showed that thermal stability of Mg3B2O6 is detected about 1380°C. Scanning electron microscopy was employed for observation of microstructure. The microstucture of obtained ceramic samples strongly depended on the magnesium source on the fabrication of Mg3B2O6 ceramic.

Structural evolution of transition metal orthoborates (Zn3B2O6−Co3B2O6) with the Kotoite mineral structure: Synthesis, structure and properties

“…Both the compounds belong to the kotoite mineral family. Kotoite structure, A 3 B 2 O 6 , (A=Mg, Mn, Co, Ni, Zn) exhibits both tetrahedral as well as octahedral coordination for the divalent cation sites [21,22,25] . Zn 3 B 2 O 6 exists in two distinct forms: α‐Zn 3 B 2 O 6 and β‐Zn 3 B 2 O 6 [26] .…”

“…Kotoite structure, A 3 B 2 O 6 , (A=Mg, Mn, Co, Ni, Zn) exhibits both tetrahedral as well as octahedral coordination for the divalent cation sites. [21,22,25] Zn 3 B 2 O 6 exists in two distinct forms: α-Zn 3 B 2 O 6 and β-Zn 3 B 2 O 6 . [26] In this study, we have investigated the β-Zn 3 B 2 O 6 phase.…”