SiO2‒CaO‒ZnO nanoglass as multifunctional material

This work focuses on the fabrication process of SiO2–CaO and SiO2–CaO–ZnO glasses. To obtain glass powders, modified Stöber sol–gel synthesis was used. The X-ray diffraction patterns and infrared absorption spectra were used to investigate the structure of materials showing that the binary system was fully amorphous while the ternary one showed partial crystallization of dicalcium silicate. The scanning electron microscopy imagining allowed to determine the morphology of glass particles as well as their composition and distribution of Si, Ca, and Zn elements in the tested samples. The final glass composition was slightly different from the assumed and was equal to 85SiO2–15CaO and 85SiO2–6.5CaO–8.5ZnO (in wt.%). The particles of both glasses were spherical, but the ones of the SiO2–CaO–ZnO sample were smaller (diameter around 100 nm) and had a narrow range of size distribution. Considering the photocatalytic properties of zinc oxide, the photocatalytic degradation of methylene blue was shown in an aqueous solution in the presence of SiO2–CaO–ZnO glass.