Synthesis of Bi4Si3O12 powders by a sol–gel method

► Bi4Si3O12 were synthesized by a sol–gel method, using stoichiometric materials. ► The calcining process of the as-dried gel was studied by different analyses. ► Phase separation in the sol–gel process was found during the calcination. Micro-crystals of bismuth orthosilicate (Bi4Si3O12) were synthesized by a sol–gel method, using stoichiometric Si(OC2H5)4, Bi(NO3)3·5H2O as the precursors and acetic acid as the solvent. The calcining process of the as-dried gel was studied by total gravity/differential scanning calory (TG/DSC), X-ray diffraction (XRD) and infrared (IR) spectra. Experiments showed that single phase of Bi4Si3O12 could be obtained by sol–gel method at a calcining temperature of 900°C. Phase separation in the sol–gel process was found during the calcination.