Estudo da influência de surfactantes nas propriedades de BaMoO4 sintetizados pela técnica hidrotérmica assistida por micro-ondas

Abstract

BaMoO4 particles were synthesized using structural drivers (surfactants) by means of the coprecipitation method at room temperature followed by the microwave assisted hydrothermal method at different times (1, 2, 4 and 8 minutes).The crystals formed acquired geometric morphologies similar to octahedra, and were structurally characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. The optical properties were investigated by photoluminescence (PL) and ultraviolet-visible (UV-vis). The X-ray diffractograms shown that the octahedra have a tetragonal crystalline structural classification of the scheelite type and without the presence of second phases. The FTIR showed active modes in the infrared region F2 (ⱱ3) and F2 (ⱱ4) which are respectively for BaMoO4 assigned to the antisymmetric stretching and bending mode modes, where F2 (ⱱ3) is related to antisymmetric Mo-O vibration within the Group [MoO4] 2- . It also indicated the characteristic band of BaMoO4 in the range of 900-800 cm-1 . Optical data from UV-Vis revealed that the values of gap energy (Egap) were around 4.27 and 4.49 eV. Field emission electron microscopy (SEM-FEG) was used to visualize and study the various morphologies of the powders. The micrographs revealed the morphological profile for the particles processed at each time, as well as the mechanism of formation and growth. The photocatalytic properties were investigated through the photocatalysis of dyes from the textile industry, which showed discoloration of the Rhodamine B dye above 70%.