Chemically vapor deposited diamond-tipped one-dimensional nanostructures and nanodiamond–silica–nanotube composites

Composite thin films of nanodiamond and silica nanotubes were synthesized by means of microwave plasma assisted chemical vapor deposition (MPCVD) on silica nanotube matrix that was seeded with nanodiamond particles. SEM, Raman spectroscopy, and EDX were used to analyze the composite. Wet chemical etching was applied to selectively remove exposed silica from the composites for further revealing the nanostructure of the composites. Nanodiamond grew around silica nanotubes and filled the space left between silica nanotubes to form a continuous film. When appropriately selected sizes of nanodiamond particles were used as diamond seeds, silica nanotubes capped with CVD-grown diamond crystals were also obtained. Potential applications and implication of composites of nanodiamond and 1-D nanostructures will be discussed.