Síntese, caracterização e investigação da atividade sonocatalítica, fotocatalítica e sonofotocatalítica de micro- e nanocristais de B-AG2Mo04

Abstract

In the present work, we report the obtaining of β-Ag2MoO4 micro and nanocrystals as well as well as the investigation of the photocatalytic, sonocatalytic and sonofotocatalytic activity. These crystals were synthesized by the controlled precipitation method from the soluble salts, silver nitrate (AgNO3) and sodium molybdate dihydradate (Na2MoO4.2H2O) without agent and tartaric acid (C4H6O6) as the chelating agent at 50 ° C for three hours. Photocatalytic, sonic and sonic activities can be analyzed for discoloration of the Rhodamine dye solution under irradiation of blue LED light. XRD patterns, Rietveld refinement data, M-Raman and FT-IR spectra indicate that all micro and nanocrystals are spinel cubic structures. The refinement results are a routine of thermal movement of Ag in the nanocrystals and a possibility in the connection angles in the octahedral groups [AgO6]. MR spectra exhibited a presence of four vibrational modes for microcrystals and five vibrational modes for nanocrystals. FT-IR spectra revealed only four vibrational modes in the region of 500 to 400 cm-1. The images of FE-SEM and STEM were presented in irregular microcrystals and in formation of several nanocrystals similar to the spheres forming superstrutures. As STEM images revealed the dense regions of agglomeration in micro and nanocrystals. In the UV-vis analysis, an evaluation of the energy band gap values of 3.31 eV (microcrystals) and 2.45 eV (nanocrystals) is presented. Finally, the sonic, photocatalytic and sonofotocatalic properties for discoloration of the Rhodamine B dye solution resulted in a good catalytic performance for the β-Ag2MoO4 crystals.