Synthesis and characterization of high NIR reflecting eco-friendly BaMoO4 pigments in scheelite family

BaMoO4 is a special type of material that is suitable for photocatalysts, scintillating medium, solid-state laser, and optical fibers applications. The effect of different methods using different precursors by ball milling and co-precipitation and their characterizations details of different BaMoO4 materials are reported here. Regardless of the employed methods, all the samples are crystallized in tetragonal symmetry with space group, I4(1)/a(88) in phase pure form. The ball-milled BaMoO4 materials show relatively broad reflections with reduced crystalline size (similar to 20 nm) than the co-precipitation methods (similar to 70 nm). Agglomerated nature of round-shaped particles is seen for the ball-milled BaMoO4 materials which differ from the morphology of the co-precipitation processed materials having different shapes and sizes in the range of similar to 227-453 nm. UV-Vis absorption results reveal the optical band gap of 3.51-4.35 eV for the different BaMoO4 materials. The Raman analysis features well support the optical properties of the BaMoO4 phase. Among the different as-prepared materials, the NIR reflectance spectrum of BaMoO4 materials obtained via the co-precipitation method exhibits relatively higher reflectance in the entire NIR region. The presently investigated BaMoO4 materials (co-precipitation) show better NIR reflectance than the other type of scheelite (BiVO4 and SrMoO4) materials.

Automated summary

This study reports the different methods and characterizations of BaMoO4 materials. Regardless of the method used, all samples have a tetragonal symmetry crystalline structure in pure form. The ball-milled BaMoO4 materials have smaller crystalline size compared to the co-precipitation method. The optical properties reveal a band gap of 3.51-4.35 eV for different BaMoO4 materials. The co-precipitation method exhibits better near-infrared reflectance for BaMoO4 materials.