磷酸盐直接共沉淀法制备K0.6Sr0.7Zr4P6O24纳米粉末

Nanometer K_0.6Sr_0.7Zr₄P₆O₂₄ (KSZP)powders were synthesized from KNO₃, Sr(NO₃)₂, NH₄H₂PO₄ and ZrOCl₂·8H₂O by direct co-precipitation method. The as-prepared precipitates and KSZP powders were characterized by thermal analysis, XRD, particle-size analyzer and SEM measurements. The results showed that the precipitates could be heat-treated at near 580 ℃ and 900 ℃, and the crystallization of the KSZP powder product depends on treatment temperature. It was non-crystalline after dried at 80 ℃, became incomplete crystalline KSZP after heat-treated at 900 ℃ and was single-phase KSZP after calcined at 1 380 ℃. The mean particle size and particle-size distribution of KSZP powder after heat-treated at 900 ℃ were smaller and narrower than those after dried at 80 ℃ and calcined at 1 380 ℃, and were 62 nm and 40～100 nm, respectively. The particle shape of the powder after heat-treatment was spheric, and the reuniting or agglomeration was found. Phosphate direct co-precipitation was more suitable than phosphate converse co-precipitation to synthesize nanometer single-phase KSZP powder and the sintered body with the nanometer powder possesses better integral sintering properties.