单晶钨纳米片/带的气相合成及其力学性能  

Vapor-phase synthesis and mechanical properties of single-crystal W nanosheets/nanobelts

作　　者：陈国良[1] 刘俊[1] 田蜜[1] 侯丽珍[2,3] 贺跃辉[2] 王世良[1,2] 董虹星[4] 

机构地区：[1]中南大学物理与电子学院,长沙410083 [2]中南大学粉末冶金国家重点实验室,长沙410083 [3]湖南师范大学物理与信息科学学院,长沙410083 [4]杭州科技职业技术学院机电工程学院,杭州311402

出　　处：《粉末冶金材料科学与工程》2013年第6期851-856,共6页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金资助项目(50804057;51074188);浙江省重中之重学科开放基金资助(20121148);浙江省教育厅科研课题(Y201327222)

摘　　要：采用气态WO2（OH）2和H2作为反应气氛，通过化学气相沉积合成厚度100~300 nm、边长10~60μm的单晶W纳米片/带，通过SEM、TEM和EDS等测试分析手段对产物的形貌、结构和元素成分进行系统表征。结果表明：晶体生长热力学（表面能最小）和动力学（竞争生长）条件分别在单晶W纳米片/带的规则几何外形和二维生长方式中起到决定性作用，据此提出了单晶W纳米片/带的生长模型。纳米压痕仪测试结果表明，Si（100）基底上W纳米片的硬度和弹性模量分别为6.3 GPa和176 GPa。分别从表面氧化层，基底与纳米片之间非理想接触和基底效应等3个方面对测试结果进行了分析和讨论。The morphology, microstructure and elemental composition of the single-crystal W nanosheets/nanobelts synthesized by chemical vapor deposition, using WO2（OH）2 and H2 as reaction precursor, were characterized by SEM, TEM and EDS. The as-synthesized W nanosheets/nanobelts have a length of 10~60μm and a thickness of 100~300 nm. The thermodynamics （surface energy minimization） and kinetics （competition growth） of crystal growth are found to be the decisive roles on the well-defined geometrical shape and two-dimensional growth of the W nanosheets/nanobelts, and a growth model for the as-synthesized W nanosheets/nanobelts is also proposed. The nanoindentation results show that the W nanosheets on Si（100） substrate exhibit a hardness of 6.3 GPa and an elastic modulus of 176 GPa. The effects of the surface oxide, the substrate effect, and the non-ideal contact between substrate and nanosheets of the measurement results are discussed.

关 键 词：钨 纳米片 化学气相沉积 纳米压痕 

分 类 号：TB302.2[一般工业技术—材料科学与工程]