Synthesis and characterization of a nickel selenide series via a hydrothermal process

详细信息    查看全文

• 作者：Azam Sobhani ; Masoud Salavati-Niasari
• 关键词：Nanoparticles ; NiSe ; NiSe2 ; Hydrothermal ; Semiconductor ; Flower-like
• 刊名：Superlattices and Microstructures
• 出版年：January, 2014
• 年：2014
• 卷：65
• 期：Complete
• 页码：79-90
• 全文大小：1568 K

文摘

A series of nickel selenides (NiSe and NiSe₂) has been successfully synthesized from the reaction of SeCl₄ with NiCl₂鈰?H₂O in the presence of cetyltrimethyl ammonium bromide (CTAB) as surfactant and hydrazine hydrate (N₂H₄鈰匟₂O) as reductant at 180 掳C for 12 h through a simple hydrothermal method. The morphology, phase structure and composition of Ni_xSe_y can be controlled by adjusting the Ni/Se ratio of the raw materials, the quantity of reductant, the reaction temperature and so forth. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) analysis. It was found that when the ratio of Ni/Se is 1:1 or 3:2, flower-like assemblies of NiSe nanosheets are formed, at 180 掳C for 12 h. When the ratio of Ni/Se is 1:2 at 180 掳C, the products are found to be the mixture of hexagonal NiSe and cubic NiSe₂. With decrease of nickel content in molar ratio of 1:2 (Ni:Se), nanospheres are agglomerated and microstructures are formed. With the reaction temperature decreasing from 180 掳C to 120 掳C, we reach pure NiSe₂ nanoparticles. The formation mechanism of the nickel selenides has been investigated in detail by means of XRD and SEM analyses.