Wet-chemical route for the preparation of lead zirconate: An amorphous carbon- and halide-free precursor synthesized by the hydrogen peroxide based route

PbZrO3 (PZ) nanoparticles were synthesized through a halide- and organic-fr ee hydrogen peroxide method at 700 degreesC for 2 h. Stoichiometric amounts of zirconyl nitrate and lead nitrate were dissolved in a diluted H2O2 (aqu eous) solution, which was slowly dropped into a solution of H2O2 and NH3 (p H = 11). The precipitate of Pb-Zr, obtained from an exothermic oxyreduction reaction, was filtered and washed to eliminate all nitrate ions. The preci pitate was dried, ground, and calcined between 300 and 1000 degreesC, for 5 min to 8 h. Tetragonal, lead-rich zirconia solid solution (t-Z) was identi fied by thermogravimetry-differential thermal analysis, X-ray diffraction, and Raman spectroscopy as an intermediate phase during the calcination proc ess, followed by the crystallization of the orthorhombic PZ phase. The aver age particle size was estimated to be 50 nm from scanning electron microsco py pictures. The change in the amount of residual t-Z phase in PZ powders w as estimated from the Raman spectra.