The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure o...The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure of the cobalt NCs were determined by XRD. The results showed that each of the cobalt nanoparticles is a single crystal with a complex cubic structure relating to the β phase of manganese. The XPS spectra indicate that the surface of Co nanoparticles was not oxidized or formed other compound. Two-dimensional order superlattices of the Co nanoparticles were formed by self-assembly technique.展开更多
The highly ordered CuO nanowire arrays of composite-oxides were synthesized within a porous anodic aluminum oxide(AAO) template by a citrate-based sol-gel route. A vacuum system was applied to draw the gel into the te...The highly ordered CuO nanowire arrays of composite-oxides were synthesized within a porous anodic aluminum oxide(AAO) template by a citrate-based sol-gel route. A vacuum system was applied to draw the gel into the template pores, which conquers the only driving force of this technique—capillary action, then the gel was thermally treated to prepare desired CuO nanowires. The results of scanning electron microscopy(SEM) indicate that the CuO nanowires are very uniformly assembled and parallel to each other in the pores of the anodic aluminum oxide(AAO) template membranes. The results of X-ray diffraction(XRD) and the selected-area electron diffraction(SAED) indicate that the CuO nanowires are monoclinic-type crystalline structure. Furthermore, X-ray photoelectron spectroscopy (XPS) demonstrates that the stoichiometric CuO is formed.展开更多
CoPt3/Co multilayered nanowire（NW） arrays are synthesized by pulsed electrodeposition into nanoporous anodic aluminum oxide（AAO） templates. The electrochemistry deposition parameters are determined by cyclic volta...CoPt3/Co multilayered nanowire（NW） arrays are synthesized by pulsed electrodeposition into nanoporous anodic aluminum oxide（AAO） templates. The electrochemistry deposition parameters are determined by cyclic voltammetry to realize the well control of the ratio of Co to Pt and the length of every segment. The x-ray diffraction（XRD） patterns show that both Co and CoPt3 NWs exhibit face-centered cubic（ fcc） structures. In the UV-visible absorption spectra,CoPt3/Co NW arrays show a red-shift with respect to pure CoPt3 NWs. Compared with the pure Co nanowire arrays, the CoPt3/Co multilayered nanowire arrays show a weak shape anisotropy and well-modulated magnetic properties. CoPt3/Co multilayered nanowires are highly encouraging that new families of bimetallic nanosystems may be developed to meet the needs of nanomaterials in emerging multifunctional nanotechnologies.展开更多
文摘The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure of the cobalt NCs were determined by XRD. The results showed that each of the cobalt nanoparticles is a single crystal with a complex cubic structure relating to the β phase of manganese. The XPS spectra indicate that the surface of Co nanoparticles was not oxidized or formed other compound. Two-dimensional order superlattices of the Co nanoparticles were formed by self-assembly technique.
基金Project(200623) supported by the Science Foundation of Shenzhen University, China
文摘The highly ordered CuO nanowire arrays of composite-oxides were synthesized within a porous anodic aluminum oxide(AAO) template by a citrate-based sol-gel route. A vacuum system was applied to draw the gel into the template pores, which conquers the only driving force of this technique—capillary action, then the gel was thermally treated to prepare desired CuO nanowires. The results of scanning electron microscopy(SEM) indicate that the CuO nanowires are very uniformly assembled and parallel to each other in the pores of the anodic aluminum oxide(AAO) template membranes. The results of X-ray diffraction(XRD) and the selected-area electron diffraction(SAED) indicate that the CuO nanowires are monoclinic-type crystalline structure. Furthermore, X-ray photoelectron spectroscopy (XPS) demonstrates that the stoichiometric CuO is formed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51472165,51471185,and 11274370)
文摘CoPt3/Co multilayered nanowire（NW） arrays are synthesized by pulsed electrodeposition into nanoporous anodic aluminum oxide（AAO） templates. The electrochemistry deposition parameters are determined by cyclic voltammetry to realize the well control of the ratio of Co to Pt and the length of every segment. The x-ray diffraction（XRD） patterns show that both Co and CoPt3 NWs exhibit face-centered cubic（ fcc） structures. In the UV-visible absorption spectra,CoPt3/Co NW arrays show a red-shift with respect to pure CoPt3 NWs. Compared with the pure Co nanowire arrays, the CoPt3/Co multilayered nanowire arrays show a weak shape anisotropy and well-modulated magnetic properties. CoPt3/Co multilayered nanowires are highly encouraging that new families of bimetallic nanosystems may be developed to meet the needs of nanomaterials in emerging multifunctional nanotechnologies.
