OPTIMIZATION OF THE SOLUTION-SOL-GEL PROCESS TO SYNTHESIZE HOMOGENEOUS BIPBSRCACUO POWDER

A criterion for optimization of the solution-sol-gel (SSG) process has been developed to synthesize homogeneous BiPbSrCaCuO powder by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX) and AC susceptibility measurements. The criterion consists of two points: (1) observation of the SSG trans ition process to ensure no precipitation of crystals during the SSG tr ansition and (2) characterization of the dry gel with XRD to ensure a gel of amorphous structure with no crystals. The criterion is verified to be effective in the synthesis of BiPbSrCaCuO powder. (C) 1997 Else vier Science B.V.