Aqueous sol–gel synthesis of nanosized ceramic composite powders with metal-formate precursors

In the present investigation, a series of multicomponent silicate systems have been prepared by using an aqueous sol–gel method, where water-soluble metal formates were used as precursors. Tetraethoxy silane and metal formates were used as precursors and water was used as solvent. The gels prepared using these precursors were calcined at different temperatures and characterized by using XRD, IR, DTA, TGA. Transmission electron microscope (TEM) was used to measure the average particle size of the calcined powders. It was observed that the average particle sizes of the powders are in nanometer scale with a narrow size distribution. In this method the replacement of metal alkoxides by metal formates and the use of water as solvent instead of alcohol, which is commonly used as solvent in all alkoxide sol–gel route facilitated the reduction of cost of the product. This processing route provides the basis for a low-cost, low-temperature method for the preparation of homogeneous nanometer-sized multicomponent ceramic powders compared with other conventional methods.