Microwave assisted preparation of Fe3+ doped β-dicalcium silicate by sol–gel method

Fe3+ doped and undoped β-dicalcium silicates (β-Ca2SiO4 or β-C2S) were prepared by sol–gel method. The gels formed were heated in a microwave oven and subsequently in a muffle furnace. The particle sizes of doped and undoped samples were found to be about 150 nm and 600 nm respectively. The materials were characterized by scanning electron microscopic, powder X-ray diffraction, BET specific area measurements, infrared spectroscopic and Mössbauer spectroscopic techniques. IR spectroscopic studies showed the possibility of distorted tetrahedral symmetry in Fe3+ doped β-C2S. Calorimetric studies have shown that iron doped β-C2S is highly reactive. From Mössbauer spectroscopic studies it is found that electronic environment of Fe3+ in β-C2S is changed due to hydration. Degree of hydration calculated from non-equilibrium water content measurements have shown that Fe3+ doped β-C2S hydrates at a much higher rate. Scanning electron microscopic studies have revealed that the hydration products in both the cases are almost identical. Formation and hydration of β-C2S in the presence of Fe3+ have been understood.