Research Article

Catalytic Chemical Vapor Deposition of Methane to Carbon Nanotubes: Copper Promoted Effect of Ni/MgO Catalysts

Figure 6

SEM images of as-produced materials grown on the catalysts (a), (b) Ni-Cu/MgO and (c), (d) Ni/MgO calcined at 500°C with reaction temperature of 650°C.
547030.fig.006a
(a)
547030.fig.006b
(b)
547030.fig.006c
(c)
547030.fig.006d
(d)