Synthesis and Characterization of Single-Walled Carbon Nanotube Silica Aerogels
Multiwalled carbon nanotubes (MWCNTs) were successfully incorporated inside silica aerogel matrix. Solid composite
materials were investigated by high-resolution transmission microscopy, scanning electron microscopy, optical spectroscopy. MWCNTs in the form of small bundles and individual tubes get locked inside the aerogel between its pores resulting in the local solution-free environment for nanotubes. Optical transmission of the composite material can be modified by the amount of the added MWCNTs. Nonlinear optical properties were studied by a Z-scan technique. Composite materials demonstrate saturable absorption for femtosecond laser pulses
at 515 nm wavelength that are attributed to the properties of
embedded nanotubes. Silica aerogels possess significantly
better thermal stability compared to polymer matrices, hosts
that are frequently used for saturable absorption applications of
carbon nanotubes. Solid and lightweight silica aerogels with
embedded nanotubes can be used as optical elements for
various photonic devices.
Photo of silica aerogel with embedded MWCNTs. Normalized
Z-scan transmittance of silica aerogel with nanotubes for two
different on-focus intensities.