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

In the present investigation, a series of multicomponent silicate systems h ave been prepared by using an aqueous sol-gel method, where water-soluble m etal formates were used as precursors. Tetraethoxy silane and metal formate s were used as precursors and water was used as solvent. The gels prepared using these precursors were calcined at different temperatures and characte rized by using XRD, IR, DTA, TGA. Transmission electron microscope (TEM) wa s 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 s cale with a narrow size distribution. In this method the replacement of met al alkoxides by metal formates and the use of water as solvent instead of a lcohol, which is commonly used as solvent in all alkoxide sol-gel route fac ilitated the reduction of cost of the product. This processing route provid es the basis for a low-cost, low-temperature method for the preparation of homogeneous nanometer-sized multicomponent ceramic powders compared with ot her conventional methods. (C) 2001 Elsevier Science B.V. All rights reserve d.