Search

Abstract: Aligned ZnO nanorod arrays were fabricated by chemical solution deposition based on Si substrate which was spin coated with ZnO colloid as nucleation seeds. Their microstructures were characterized by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The results indicated that ZnO nanorods nucleated and grew vertically on Si substrates along the [001] direction with single-crystalline structure. The diameter of ZnO nanorods was greatly affected by the grain size of ZnO seeds. Room-temperature photoluminescence of nanorods has a strong emission band at about 384nm. [Copyright &y& Elsevier]

Abstract: A typical naturally occurring mineral, marine manganese nodule, could be developed as a catalyst for the catalytic chemical vapor deposition synthesis of helical carbon nanotubes by changing the experimental conditions. In the product, a novel one-dimensional carbon nanostructure with triple helices was first observed. The possible origin is briefly discussed. It points out a facile method to obtain helical carbon nanostructures. [Copyright &y& Elsevier]

Abstract: The preparation of multi-walled carbon nanotubes (MWCNTs) by chemical vapor deposition (CVD) method using nanocrystalline CaCO3 as metal catalyst support was investigated, where acetylene was used as carbon source, and Co, Fe and Ni, as well as their bimetallic compounds as the active component of the catalyst. The smaller size of the CaCO3 support led to a much higher yield of CNTs than previously reported. It was noteworthy that the best performance was Fe-Co nanoparticles, which gave a high yield of CNTs, as judged by experimental results. Growth temperature affected catalytic activity and the disintegration of the support. The raw product was purified to a high level, with little damage on the CNT structure, as confirmed by thermal gravimetric (TG), micro-Raman and transmission electron microscopy (TEM) analyses. [Copyright &y& Elsevier]

Abstract: Nickel nanoparticles were prepared and uniformly supported on multi-walled carbon nanotubes (MWCNTs) by reduction route with CNTs as a reducing agent at 600°C. As-prepared nickel nanoparticles were single crystalline with a face-center-cubic phase and a size distribution ranging from 10 to 50nm, and they were characterized by transmission electron microscopy (TEM), high-resolution TEM and X-ray diffraction (XRD). These nickel nanoparticles would be coated with graphene layers, when they were exposed to acetylene at 600°C. The coercivity values of nickel nanoparticles were superior to that of bulk nickel at room temperature. [Copyright &y& Elsevier]

Short multi-wall carbon nanotubes (MWNTs) with open tips were obtained by mechanical ball milling. The microstructure characteristics of MWNTs before and after ball milling were checked by transmission electron microscopy (TEM). The effect of ball milling on the hydrogen adsorption behavior of the MWNTs was studied. The hydrogen adsorption experiments were carried out at room temperature under a pressure of 8–9 MPa. The hydrogen adsorption capacity of carbon nanotubes milled for 10 h was 0.66 wt%, which was about six times that of MWNTs without milling. For the carbon nanotubes milled with MgO for 1 h, a hydrogen adsorption capacity of 0.69 wt% was obtained. The enhancement of hydrogen adsorption might result from the increase of defects and surface area of the MWNTs caused by ball milling. [Copyright &y& Elsevier]