Dual-template Assisted Synthesis of Silica Nanotubes

Silica nanotubes were synthesized via sol-gel process using poly(ethylene glycol) functionalized multi-walled carbon nanotubes (MWNT-PEG) as the dual templates. Through the hydrolysis of tetraethoxysilane (TEOS), a continuous coating of silica was deposited over the MWNT surfaces to form core-shell structures. Hollow silica nanotubes were finally obtained by removal of core carbon components through calcination. The as-prepared hollow silica structures were characterized by electron microscopy, energy dispersive X-ray spectrometry and infrared spectroscopy. The synthesized silica nanotubes might find potential applications in many fields such as encapsulation, catalysis, biological separation, and sensing.