Fe, Co, and Ni are catalytically effective for growing single-walled carbon nanotubes (SWNTs). On substrates, however, Ni tends to yield only multi-walled carbon nanotubes. Because enhanced surface diffusion at the elevated growth temperature required for deposition might cause coarsening of Ni catalyst nanoparticles, adjusting the nominal Ni thickness should be crucial for controlling the part...

Hydrothermal liquefaction (HTL) of microalgae Nannochloropsis (NAS) over various transition metal M/TiO2 (M = Fe, Co, Ni, Mo, and Mn) was investigated. Ni/TiO2 was the most effective catalyst to improve the yield and quality of biocrude and the liquefaction conversion. Ni/TiO2 was characterized by XRD, XRF, and XPS. The research of Effect of reaction temperature on HTL of NAS over Ni/TiO2 sugge...

We demonstrate a new strategy for tuning the size of large-diameter and few-walled nitrogen-doped carbon nanotubes (N-CNTs) from 50 to 150 nm by varying the transition metal (TM = Fe, Co, Ni or Mn) used to catalyze graphitization of dicyandiamide. Fe yielded the largest tubes, followed by Co and Ni, while Mn produced a clot-like carbon morphology. We show that morphology is correlated with elec...

We present the temperature dependence of the growth rate of carbon nanofibers by plasma-enhanced chemical vapor deposition with Ni, Co, and Fe catalysts. We extrapolate a common low activation energy of 0.23-0.4 eV, much lower than for thermal deposition. The carbon diffusion on the catalyst surface and the stability of the precursor molecules, C2H2 or CH4, are investigated by ab initio plane w...

Block copolymer micellar templates were used for the controlled synthesis of large arrays of mono-metallic (Fe, Co, Ni, Mo) and bi-metallic (Fe–Mo) nanoparticles with average diameters ranging from 1 to 4 nm and the distance between the nanoparticles ranging from 40 to 45 nm. XPS data reveal the presence of mono-metallic nanoparticles in their oxidized states. These uniform arrays of nanopartic...

Reaction of the mononuclear Ni(II) thiolate complexes [Ni(L)] [L, L(1), H2L(1), bis(2-mercaptoethyl)-1,2-dimercaptoethane; L(2), H2L(2), N,N'-dimethyl-N,N'-bis(2-mercaptoethyl)-bis(aminoethyl)sulfide] with [FeCp(CO)2I] gives the dithiolate-bridged heterobimetallic species, [Ni(L(1))FeCp(CO)]PF6, 1, and [Ni(L(2))FeCp]I, 2, respectively. Binding of a Fe(CO)3 fragment via reaction of square-planar...

This study focuses on the manufacture of carbon nanotubes using the arc discharge method. Several independent variables were changed, such as the current (80 and 100 A), an atmosphere of open air or argon and the catalyst (no catalyst, Fe or a mixture of Fe/Co,Ni). Only one set of parameters yielded MWNTs, involving Fe as the catalyst and an open air atmosphere. I. INTRODUCTION There has been i...

Large scale synthesis of carbon nanofibres (CNFs) on a sodium chloride support has been achieved. CNFs have been synthesized using metal oxalate (Ni, Co and Fe) as catalyst precursors at 680 C by chemical vapour deposition method. Upon pyrolysis, this catalyst precursors yield catalyst nanoparticles directly. The sodium chloride was used as a catalyst support, ...

The oxygen reduction reaction (ORR) is one of the major factors that is limiting the overall performance output of microbial fuel cells (MFC). In this study, Platinum Group Metal-free (PGM-free) ORR catalysts based on Fe, Co, Ni, Mn and the same precursor (Aminoantipyrine, AAPyr) were synthesized using identical sacrificial support method (SSM). The catalysts were investigated for their electro...

monometallic and bimetallic ni and co catalytic nanoparticles supported on titanium dioxide (rutile phase) substrate were prepared by wet impregnation method. these nanoparicles were used as catalysts for synthesis of multiwalled carbon nanotubes (mwcnts) from acetylene decomposition at 700°c by the catalytic chemical vapor deposition (ccvd) technique. the nanomaterials (catalyst and cnts) were...