Thermal Diffusivity Measurement of MoS₂ & MoS₂-GO Nano-Composite By Photoacoustic Spectroscopy

Abstract

Photoacoustic spectrometer (PAS) is a significant technique to measure the thermal diffusivity of any material. When modulated light interact with solid sample which is covered by aluminium or other metal plate, first the light is absorbed by the sample and then thermal energy emitted due to non-radiative decay. Thereafter, acoustic wave produced due to different temperature which maintain by an optical chopper. The medium inside the cavity expands or retract according to the chopper frequency. So, the generated pressure fluctuation inside it measures by using a sensitive condenser microphone which fitted inside the cavity by a narrow path. Here the authors successfully synthesized molybdenum disulfide (MoS2) and its nanocomposite with graphene oxide (MoS2-GO) by simple hydrothermal method. The XRD and FESEM data confirm the phase and morphological structures of the synthesized material. The thermal diffusivity of MoS2 and MoS2-GO nanocomposite are obtained 10.94 mm2/s and 14.72 mm2/s respectively.

Fabrication of a photoacoustic cell and thermal diffusivity measurement of graphene oxide using photoacoustic spectroscopy

“…12 Through PAS the thermal diffusivity could efficiently be measured and it is also used as multi-purpose spectroscopic technique in variety of scientific fields. [13][14][15][16][17] With the advent of lasers and sensitive acoustic sensors the sensitivity of PAS has now improved too much.…”

“…Schmitt et al 14 have measured the thermal diffusivity of caprocks and Jeyadheepan et al 15 have measured the thermal diffusivity of Cd 2 SnO 4 thin films using this technique. Sarkar and Kumar 16,17 have measured the thermal diffusivity of MoS 2 , MoS 2 -GO nano-composites, and carbon black samples. Authors have found that the addition of GO in MoS 2 increases the thermal diffusivity and this result has inspired authors to measure thermal diffusivity of graphene oxide (GO).…”