Synthesis and characterization of low cost nanosilica from sodium silicate solution and their applications in ceramic engobes

Nanosilica (NS) powders were synthesized from sodium silicate solution (SSS) and their effects on ceramics engobes were investigated. Synthesized NS powder was subjected to various characterization studies by transmission electron microscopy (TEM), X-ray diffractometry (XRD), X-ray fluorescence spectroscopy (XRF), Brunauer-Emmett-Teller (BET) method, Fourier transform infrared measurements and gravimetric/differential thermal analysis (TGA and DTA) techniques. The results indicate that the synthesized NS consisted of pure silica particles (96.8%) with the particle size in the range 8.64-18.31 nm, amorphous structure having surface area 160.29 m(2)/g and the thermal analysis show that the weight losses of 6.23. The study showed that NS powder significantly improved physico-chemical properties of prepared ceramics engobes such as whiteness, thermal expansion coefficient (TEC), the crystallinity, water absorption (WA), linear shrinkage (LSH), breaking strength and bulk density (BD). The study can serve as theoretical basis for further traditional ceramics applications of NS powder. The best results were found when the NS powder content increases, whiteness as well as linear shrinkage increased whereas thermal expansion coefficient, water absorption and bulk density decreased. (C) 2019 Published by Elsevier Espana, S.L.U. on behalf of SECV.