Carbon Nanotubes in water, investigation of heat and mass transfer phenomena with Molecular Dynamics and Pump and Probe spectroscopy.

The recent developments of Carbon Nanotubes (CNTs) are of vital importance for nanothermal and nanofluids applications, such as heat sinks and desalination membranes. Due to their significance, it is needed to investigate their properties accurately with modeling and experimental techniques. When it comes to heat transfer, it is fundamental to interpret the role of the Thermal Boundary Resistance (TBR) and the vibrational properties of the system. Moreover, considering Carbon Nanotubes in a water solution, the effect of nanoconfined water formed at their boundary is believed to be relevant in both energy and mass transfer phenomena. In this work, it is reported an investigation of the thermal behavior of Carbon Nanotubes in an aqueous solution by means of Molecular Dynamics simulations and the early results of Pump and Probe spectroscopy. In particular, Molecular Dynamics simulations are performed to investigate the role of the interface in heat and mass transfer phenomena. Firstly, it is proposed a sensitivity analysis with different surface wetting parameters to study: thermal relaxation of excited Carbon Nanotube, water density profiles, arrangements of water molecules in the structure and vibrational spectra. This analysis is carried out on different sizes of nanotube with chirality (5,5) and (10,10). From an energetic standpoint, spontaneous water entrance in the CNT pore is examined for a (5,5) system by means of the Potential of Mean Force. Once a suitable wetting parameter is assumed, it is investigated the thermal behavior of an OH Functionalized (10,10) CNT to reproduce experimental samples correctly. To conclude, it is provided an outline of the early results of Carbon Nanotube in aqueous solution investigated with Pump and Probe spectroscopy with testing developed at the Institut Lumière Matière of Lyon.