Rapid synthesis of A2(MoO4)3 (A = Y3+ and La3+)with a CO2 laser

Negative thermal expansion material of yttrium molybdate and positive thermal expansion material of lanthanum molybdate have been successfully synthesized by rapid solidification with a CO2 laser. Both materials were solidified in densely packed blocks with smooth surface and glazing color. They have similar microstructures consisting of nano-particles or nano-dendrites with grain sizes around 20–30 nm. Raman spectroscopic and XRD analyses reveal that lanthanum molybdate crystallized in a high temperature phase of tetrahedral La2Mo3O12, whereas yttrium molybdate crystallized in an orthorhombic Y2Mo3O12. This synthetic route is a very rapid process with which a sample can be synthesized within a few seconds and holds prospect for the synthesis of other rare earth molybdates and tungstates.

Graphical abstractLanthanum molybdate shows similar microstructure as yttrium molybdate but they crystallize in different phases (tetrahedral for La2Mo3O12, and orthorhombic forY2Mo3O12).Figure optionsDownload full-size imageDownload as PowerPoint slide