Příprava a využití nanočástic ZnS a CdS pro fotokatalytický rozklad fenolu ve vodných roztocích

Abstract

Phenol is one of the dangerous organic pollutants which are present in industrial waste waters. The aim of this thesis was synthesis of ZnS and CdS nanoparticles in different ways that were be used for photocatalytic dissociation of phenol in aqueous solutions. Nanoparticles were prepared in the presence of surfactant CTAB and then they were deposited on the clay phyllosilicates montmorillonite (MMT). Nanoparticles were studied by UV-VIS spectrophotometry, it was used to find the band gap energy, and transmission electron microscopy. Prepared nanocomposites ZnS- MMT and CdS-MMT were applied for photodegradation of phenol for different times (from 2 minutes to 3 hours). The experiments were taken in a home-made apparatus in the presence of the UV light. The concentration of phenol before decomposition and after decomposition was measured by spectrophotometry. For comparison, the same experiments with commercial photocatalyst TiO2 Degussa P25 and the decomposition by UV light in absence of photocatalyst were performed as well. The final products were analyzed by gas chromatography and it was found that the phenol is oxidized to carbon dioxide.