水热法合成硼酸钙的场发射扫描电镜分析

FE-SEM Studies on Calcium Borates Synthesized by Hydrothermal Method

以工业硼酸、硼砂和氧化钙为原料,通过改变反应温度和原料配比,用水热法合成了系列硼钙化合物。根据化学分析和XRD分析数据确定了各种合成产物的化学组成、物相名称,用场发射扫描电镜(FE-SEM)对六种硼酸钙的显微形貌、颗粒大小进行了表征,发现它们的显微形貌、颗粒大小有很大的不同。CaO.3B2O3.5H2O呈条板状,厚度在100~300 nm之间;2CaO.5B2O3.5H2O呈大纳米薄片,厚度在50~100 nm的居多;2CaO.3B2O3.H2O则是纳米细线,直径在100 nm左右;4CaO.5B2O3.7H2O呈小纳米薄片状,厚度在100 nm左右;2CaO.B2O3.H2O呈球粒状,大小在500 nm^1μm;CaO.B2O3呈粗针状,粗、细端直径在150~300 nm之间。

A series of calcium borates were hydrothermally synthesized at different temperature using boric acid, borax and calcium oxide as raw materials. Chemical components and phase composition were determined by chemical and XRD analysis. Field-emission scanning electron microscope （FESEM） was employed to characterize the micro-morphologies and particle sizes of the six kinds of calcium borates. The results indicate that various calcium borates synthesized at different conditions have different phase compositions, micro-morphologies and particle sites. Lathy-shaped CaO·3B2O3·5H2O has the thickness of 100-300 nm. 2CaO·5B2O3 ·5H2O is big nano-lamellar shaped with thickness of 50-100 nm. 2CaO· 3B2O3 -H2O nanowire has the diameter of about 100 nm. 4CaO ·5B2O3 ·7H2O appears a shape of small nano-lamellar with thickness of 100 nm. 2CaO·B2O3·H2O appears spherical shape with diameter of 500 nm-1 μm and acicular-shaped CaO·B2O3 has thick and thin end between 150-300 nm.