采用高温氮化合成的热化学方法制备了单晶的线型和带型α-Si3N4准一维结构.其中线型α-Si3N4准一维结构沉积在温度较低的反应区域(1200℃)，而带型α-Si3N4准一维结构则沉积在高温原料源附近位置(1450℃).经XRD、SEM、TEM、HRTEM分析表明,制备的线型和带型α-Si3N4准一维结构均为单晶；线型α-Si3N4直径约为100~300nm,长为几十微米；而带型α-Si3N4厚约30nm,宽度在300nm~2μm之间，长度为几微米到几十微米.从晶体生长热力学及动力学方面讨论了线型和带型α-Si3N4准一维结构的生长过程和分区沉积的原因.结果表明，较高的温度和过饱和度有利于形成带型准一维结构.
Large quantities of wirelike and beltlike α-Si3N4 quasi-one-dimension structure were synthesized via direct reaction of SiO powder with N2 at 1450℃ using chemical vapor deposition. The wirelike α-Si3N4 was deposited at lower temperature region (1200℃), while the beltlike α-Si3N4 was deposited at higher temperature region (1450℃). The mean diameter and length of wirelike α-Si3N4 are about 100-300 nm and tens of micrometers, respectively. And the beltlike α-Si3N4 is tens of nanometers in the thickness, 300nm-2μm in the width and several micrometers to tens of micrometers in the length. HRTEM image and SAED pattern of the wirelike and beltlike α-Si3N4 show that they are single crystalline, and beltlike α-Si3N4 grows along ［210］ direction. Wirelike and beltlike α-Si3N4 quasi-one-dimension structure grow by the VS process. Results show that high deposition temperature and supersaturation favors the formation of beltlike quasi-one-dimension structures; while low deposition temperature and supersaturation tend to form wirelike quasi-one-dimension structures. Therefore, the morphology of microstructure materials could be controlled through regulating the deposition temperature and supersaturation in the chemical vapor deposition process. The experiment may offer reference for controlled synthesis preparation of quasi-one-dimension structures.
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