Single-step synthesis and characterization of single-walled carbon nanohorns hybridized with Pd nanoparticles using N2 gas-injected arc-in-water method

Simultaneous esterification and transesterification for biodiesel synthesis by a catalyst consisting of sulfonated single-walled carbon nanohorn dispersed with Fe/Fe2O3 nanoparticles

“…It was also reported that the impregnation of acid functional groups on SWCNH surface induced the increase of mesopores, leading to greater catalytic performance by promoting the diffusion of reactants inside the catalyst. This study employs SO 3 This structure can be prepared using the products synthesized by gas-injected arc-in-water (GI-AIW) method, which enables ones to fabricate SWCNH dispersed with various kinds of active metal nanoparticles (Pd [19], Pt [20] and Ni-Pd alloy [21]) in a single step. Among the metallic components, we focus Fe because it is reported that a catalyst containing a kind of iron oxide (magnetite) can exhibit the high activity for esterification and transesterification [16].…”

Impacts of Calcination Temperature on Preparation of a Solid Acid Catalyst by Sulfonation of Single-Walled Carbon Nanohorns Dispersed with Iron Nanoparticles

“…The dark spots whose diameters range from single nanometers to approximately 25 nm dispersed in SWCNHs are considered to be nanoparticles of body-centered-cubic (bcc) Fe, as explained later. Most of these Fe nanoparticles should exist inside SWCNHs analogically to the SWCNHs dispersed with Pd nanoparticles previously synthesized in the same manner (Poonjarernsilp et al, 2011). Thus, it can be expected that Fe nanoparticles in our products could be protected from oxidation by the barrier effect of SWCNHs, unless pores are newly opened on them.…”

“…dispersed with Fe nanoparticles synthesized by GI-AIW method Initially, Fe-SWCNHs were synthesized by the GI-AIW method, which can be referred to in previous reports (Poonjarernsilp et al, 2011). In this method, the graphite rods of the cathode (20 mm in diameter) and the anode (6 mm in diameter) (99.9995%, Alfa Aesar) were placed coaxially in the vertical direction in water at room temperature.…”

“…To date, we have developed a method, the so-called gas-injected arc-in-water (GI-AIW) method (Sano, 2004), to prepare SWNCHs hybridized with active metals, e.g., Pd, Pd-alloys, Fe, etc. (Poonjarernsilp et al, 2011(Poonjarernsilp et al, , 2015Sano et al, 2012Sano et al, , 2014. It has been found that SWCNHs dispersed with Fe (Fe-SWCNHs) prepared by this method can be used to prepare a magnetic solid acid catalyst if they are subjected to a two-step process, including an acid impregnation step using concentrated sulfuric acid, and a subsequent calcination step in air (Poonjarernsilp et al, , 2015.…”

Comparative study of nanocarbons synthesized between electrodes in liquid phase by solution plasma

“…Electric discharge in liquid media is a versatile method for the synthesis of metal nanoparticles, [1][2][3] bimetallic nanoparticles, 4) nonmetal catalysts, [5][6][7] carbon nanospheres (CNS), 8) graphenes, 9) carbon nanotubes, [10][11][12][13] carbon onions, 14) metal nanoparticles covered by carbon, 15,16) mesoporous silica, 17) and polymers. 18) Among these, nonmetallic carbon catalysts have attracted a great deal of attention as a Pt substitute material in energy storage devices such as secondary batteries 19) and supercapacitors 20,21) for smart grids or electric automobiles.…”