Abstract
In the research field of piezo-catalytic material, the primary way of degradation process is mixing powder materials with dye solution directly. The color variation of dye solution is easy to be observed. In our previous work, MoS2 (Molybdenum disulfide) nanoflowers have highly piezo-catalytic properties. However, the greatly specific surface area of MoS2 nanoflowers results in the significant adsorption effect, which will hinder the analysis of degradation. In this study, we reported a new way of degradation, we mixed MoS2 nanoflowers with Di water and then ultrasonically vibrated for a period of time. Finally, we used centrifuge to separate the powder and solution, which was confirmed by simple measurement that over 99 % of the powder was removed. There would be a little single- and few- layered MoS2 nanoflowers remained in the solution and we found that the solution was catalytic. The catalytic properties of as-prepared solution were found to be proportional to the amount of MoS2 nanoflowers we added. The catalytic activity of the solution for decomposing Rhodamine B (RhB) solution could reach 80 % when 250 mg of the MoS2 nanoflowers was added. We could ignore the adsorption effect because of the 99 % removal of the powder. Therefore, OH radicals degradation mechanism could be regarded as the primary mechanism. The florescent spectra indicated the concentration of OH radicals in our as-prepared solution increases with the increasing amount of the MoS2 nanoflowers we added. The lifetime of OH radical in our as-prepared solution is up to five hours according to our observation. Our team thought that it is because of the F-center defects, which contributed to the amazingly long lifetime of OH radical.