Preparation and Characterization of Silicate-1@Kaolin Clay Ceramic with Different Na+ Concentration

In order to explore the synthesis of silicate-1 membrane on kaolin clay ceramic and the effect of Na+ ion substitution on the dielectric properties of ceramic, silicate-1@ kaolin clay ceramics containing different content of Na+ were successfully synthesized by combining sintering, sol-gel, and ion exchange method. Samples were analyzed by chemical composition (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM), digital hardness tester, and microwave dielectric measurement system. SEM images exhibited that a layer of silicate-1 was successfully grown on the surface of the kaolin clay ceramic. The energy dispersive spectrometer (EDS) revealed that the content of Na+ in silicate-1 decreased with increase of ion exchange time. The content of Na+ in silicate-1@ kaolin clay ceramic decreased from 1.46 to 0.29% when the silicate-1@ kaolin clay ceramic was treated by the unsaturated solution of NH3 from zero to two times. In this process, the dielectric constant of the silicate-1@ kaolin clay ceramic almost kept the same. But the dielectric loss of silicate-1@ kaolin clay ceramic decreased from 0.474 to 0.131. Silicate-1@ kaolin clay ceramic is expected to be used as sensor to detect some metal ions.