Research On Hydrothermal Synthesis Of One-Dimension PZT And Its Growth Mechanism

PZT one-dimension structure was successfully synthesized by using ZrOCl₂·8H₂O/Zr(NO₃)₄·5H₂O/ZrO(No₃)₂·2H₂O, Pb(NO₃)₂/Pb(CH₃COOH)₂ and Ti(C₄H₉O)₄ as raw materials, ammonia as precipitator, KOH as minerizer and CTAB/PVA 1750 as surfactant in hydrothermal system. XRD, RAMAN, SEM and TEM were used to characterize phase composition and microstructure of the products .By adding CTAB, we concluded that the proper concentration of CTAB to produce PZT one-dimension structure was 5g/L. The morphology was nanorods with 500nm in width and 8μm in length. As the reation time increased from 12h to 48h, the amount of PZT one-dimension structure was getting more. We proposed that the crystal growth and morphology evolution was governed by dissolution-precipitation process. The value of pH producing Zr-Ti precipitation was chosen as 9.5, 10, 10.5 and 11 to investigate the influence on the mophorlogy of powders. It showed that as the the value of pH increased from 9.5 to 11, ratio of length/width increased from 2 to 8. The growth tropism of single nanorod was along [001] characterized by TEM. According to the experiments, the mechanism that CTAB works on PZT one-dimension structure was studied and a model was set up to explain the mechanism.By adding PVA 1750, we concluded that as the concentration of PVA 1750 got higher, the trend of producing PZT one-dimension got more obvious, and the ratio of length/width got higher. As the concentration of PVA 1750 rose to 16g/L, the morphology of PZT was nanorods with 300nm in width and 2.5μm in length. We also concluded that the Zr-Ti precipitation and the production cleaned by centrifugation would be prior to produce PZT one-dimension strcture. The effects of reaction time and the value of PH producing Zr-Ti precipitation on the morphology of powders was the same as adding CTAB. It indicated that the concentration of KOH played an important role on the morpgology of powders. When the concentration of KOH was lower (1.48mol/L), the morphology was furcate, while the concentration of KOH was higher (2mol/L), the morphology was radiate nanorods surrounding a sphere. The growth tropism of single nanorod was along [001] characterized by TEM. According to the experiments, the mechanism that PVA 1750 works on PZT one-dimension structure was studied and a model was set up to explain the mechanism.