Structural characterization and visible light activated photocatalytic ability of glass–ceramics prepared from municipal solid waste

The relationship between local structure and visible-light-activated photocatalytic ability of glass–ceramics prepared from Municipal Solid Waste (MSW) was investigated. The samples were characterized by XRD, 57Fe Mossbauer spectroscopies, TEM and DRS. From the Mossbauer spectrum, it was found that iron ions are present in FeIII(tetrahedral) and FeII(tetrahedral) coordinations. A high covalent iron magnetic component (FeIV) with small isomeric shifts is also confirmed in the Model Slag (MS-x) samples. The energy band gap values of the samples can easily be tuned by simple adjusting the initial iron concentration and heat treatment. The largest degradation of 99.56% was estimated for methylene blue dye under the visible-light irradiation using MS-15. It is concluded that a small change of chemical composition in MSW contributed to a large change of first-order-rate kinetics and local structure. This study provides a novel approach for the removal of contaminants using MSW and sheds new insights into the presence of FeIV species enhancing photocatalytic activity.