Infrared absorbance of vertically-aligned multi-walled CNT forest as a function of synthesis temperature and time

• In this paper, the growth of optimized vertically aligned multi-walled carbon nanotube (VA-MWCNT) forests by LPCVD method for use in a large-area absorber in infrared detectors is presented. The effect of synthesis temperature (500−700 °C) and time (1−10 min) on the optical absorption coefficient in the infrared (2−20 μm) is investigated by FT-IR measurement at various incident angles (15-80°). The structural properties of VA-MWCNT are characterized by SEM, TEM and Raman spectroscopy. Spectral measurements show an increasing absorption with the height of the forest that results at increased synthesis time and temperature. However, the absorption coefficient decreases with increasing synthesize time and temperature, while it is also affected by other properties, such as diameter, density, alignment, and uniformity. Moreover, the reduction in absorption at oblique incident angles demonstrates the relevance of surface properties. Finally, a circular graphite waveguide system is used to model the absorption characteristics of an MWCNT forest.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

NATURVETENSKAP  -- Fysik -- Annan fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Other Physics Topics (hsv//eng)

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

VA-MWCNT

Growth temperature

Forest

Growth time

Infrared

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)