Zn2SO4（OH）2·2H2O与ZnO晶须的制备及其生长机制

摘要

Using Zn2 SO4 ·7H2 O,NaOH as raw material,high-quality Zn2 SO4 (OH)2 ·2H2 O and ZnO whisker was synthesized via liquid precipitation reaction and sintering methods process.The phase,gran-ularity,structure of crystal morphology of whiskers samples were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM)and thermal analysis (TG-DTA).The SEM result re-vealed that :① the whiskers formed with fine dispersive capability,② the crystal formed with good whisker quality,③ the surface was smooth,and ④ the particle was dispersed in uniform distribution. From the point of growth units,the growth mechanism of Zn2 SO4 (OH)2 ·2H2 O whisker was investigated in this work.The growth unit of Zn2 SO4 (OH)2 ·2H2 O whisker is[Zn-(OH)6 ]4 -.The growth process of whisker was determined to be [Zn - (OH)6 ]4 -and HSO -4 piles up towards one-dimensional direction and eventually forms whiskers.After thermal decomposition,the morphology was the same,and Zn2 SO4 (OH)2 ·2H2 Owhiskers eventually became the ZnO whiskers.%以 Zn2 SO4·7H2 O 为原料，NaOH 为沉淀剂，采用液相沉淀及烧结方法制备了 Zn2 SO4（OH）2·2H2 O与 ZnO 晶须，样品采用 XRD、SEM及 TG-DTA 等对样品物相、形貌及热行为进行了表征，结果表明晶须品质优良：其分散性好，粒度分布均匀、表面光滑。又从“生长基元”角度出发，讨论了 Zn2 SO4（OH）2·2H2 O 晶须的形成机制，其生长过程是生长基元八面体[Zn －（OH）6]4－与 HSO －4往某一晶面稳定叠合生长的结果， Zn2 SO4（OH）2·2H2 O 晶须经热分解后，其形貌不变，最终变为 ZnO 晶须。