Controlled Synthesis Of BaMoO₄and BaCrO₄Microcrystals In The Presence Of PSS And PSMA From Aqueous Solution

In this article, Barium chromate (BaCrO4) and Barium molybdate (BaMoO4)with various morphologies were synthesized in the presence of poly (sodium4-styrenesulfonate)(PSS) and poly-(styrene-alt-maleic acid)(PSMA), at room temperature, from aqueous solutions. We mainly introduced four aspects including:BaCrO4microcrystals with various morphologies such as shuttle-like, X-shaped, ellipsoid, leaf-like crystals were synthesized in the presence of PSS. BaMoO4microcrystals with various morphologies such as sphere-like and octahedra crystals were synthesized in the presence of PSS as a growth agent. BaCrO4microcrystals with various morphologies such as flower-like, sphere, barrel-shaped, hexagon crystals were synthesized in the presence of PSMA. BaMoO4microcrystals with various morphologies such as flower-like spheres, spindle-like crystals and octahedrons crystals were synthesized in the presence of PSMA. The as-prepared products were characterized with field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and photoluminescence (PL) spectrometer. The results show that the PSS and PSMA had very distinct effects on morphology evolution of BaCrO4and BaMoO4. And the concentrations of reactants, concentration of PSS or PSMA, reaction time and pH values turn out to be essential parameters in morphology and size evolution of BaCrO4and BaMoO4. The possible formation mechanisms of BaCrO4and BaMoO4crystals with different morphologies were proposed. PSS and PSMA complexed Ba2+first, formed Ba-PSS or Ba-PSMA, then released places for MoO42-or CrO42-In these processes, they affect the nucleation and crystallization process by interacting with the face of crystal, which finally results in various morphologies and sizes of crystals. In addition, the possible analysis of photoluminescence (PL) spectra was also proposed. The PL spectra of as-prepared BaCrO4microcrystal controlled by PSS and PSMA have a green emission peak range of527-530nm. The PL spectra of BaMoO4controlled by PSS exhibited a strong blue emission at around404-413nm. The PL spectra of BaMoO4controlled by PSMA have a strong green emission at530nm. This study also showed that the energy transitions, the morphology and size of crystals, and the surface defects were vitally important to the PL intensity of BaCrO4and BaMoO4. In addition, our research may be extended to synthesis other inorganic materials with novel morphologies.