Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Solvothermal synthesis of uniform bismuth nanospheres using poly(N-vinyl-2-pyrrolidone) as a reducing agent | Wu et al. Nanoscale Research Letters 2011 6 66 http content 6 1 66 o Nanoscale Research Letters a SpringerOpen Journal NANO IDEA Open Access Solvothermal synthesis of uniform bismuth nanospheres using poly N-vinyl-2-pyrrolidone as a reducing agent Jiliang Wu 1 Fan Qin1 Zhong Lu1 Hai-Jian Yang2 Rong Chen1 Abstract Uniform bismuth nanospheres were successfully prepared from bismuth nitrate in the presence of poly N-vinyl-2-pyrrolidone PVP by solvothermal process. The product was characterized by powder X-ray diffraction scanning electron microscopy transmission electron microscopy selected area electron diffraction and energy-dispersive X-ray. PVP plays a critical role both as a reducing agent and a capping agent in the formation of bismuth nanospheres. Shape and size of bismuth nanospheres could be tuned by changing the employed PVP bismuth salt ratio. It was also found the solvent had an effect on the morphologies of bismuth nanomaterials. The possible formation and growth mechanism of bismuth nanospheres were also discussed and proposed to explain the reduction step. Introduction Recently metal nanostructures with functional properties have been extensively studied due to their wide applications. Among the various metal nanostructures monodisperse metallic nanospheres have attracted considerable attention because of their unique optical catalytic as well as novel chemical and biological properties 1-8 . For example the controlled silver nanospheres were applied for optical studies and antibacterial applications 9 10 . Thus much effort has been devoted to the preparation of new metal nanospheres and their functional transformation 11-14 . As a semimetal bismuth has unusual properties due to its highly anisotropic Fermi surface low carrier densities small carrier effective masses and long carrier mean free path 15 . Bismuth nanostructures have received steadily growing interests since they play important roles in many diverse applications 16
