低温湿化学法可控制备一维Te纳米线/棒

Controlled Preparation of Te Nanowires/Nanorods by Low Temperature Wet Chemical Methods

采用低温湿化学法制备了形貌可调的Te纳米线/棒.考察了反应温度和还原剂滴加速率对产物的物相和微观结构的影响规律.研究结果表明,随着反应温度的升高,Te纳米线的长度逐渐变小,直径逐渐增大;随着还原剂滴加速率减慢,产物Te纳米线长度增加,直径增大.通过考察不同反应阶段产物的形貌和结构,可推测Te纳米线/棒的生长模式为:反应初期,溶解在乙二醇内的TeO2被还原为亚稳态的活性α-Te和稳态的τ-Te,随着反应的进行,亚稳态的活性α-Te将重新溶解,并被还原为稳态的τ-Te析出.τ-Te沿[001]方向轴向生长的特性应归因于其晶体的各向异性.

In the present work, Te nanowires/nanorods were prepared by low temperature wet chemical methods. The effects of reaction temperature and the dropping rate of reducing agent on the phase and microstructure of the products were investigated. The results showed that the diameter of Te nanowires increased and the length decreased with the increase of reaction temperature. With decreasing the dropping rate of hydrazine hydrate, the length and diameter of the Te nanowires all increased. The growth principle of Te nanowires could be inferred by observing the morphology and structure of the products during different reaction stages. At early stage of the reaction, the TeO2 dissolved in ethylene glycol were reduced into the metastable activated α-Te and stable τ-Te. As the reaction proceeded, metastable α-Te would be re-dissolved and be reduced into the stable τ-Te. The axial growth characteristic along [001] direction of τ-Te crystal should be ascribed to its significant crystal anisotropy.