Investigation of interaction of some MXene structures with organic molecules

Transition metal carbides, nitrides or carbonitrides, known as MXene materials, have been the focus of attention in recent years due to the wide range of applications in the two dimensional materials family. Since its synthesis in 2011, the properties of these structures have been investigated in terms of various applications such as lithium ion batteries, super capacitors, catalysts, photocatalysis, field effect transistors and biomedical. However, there is a potential for research in the biomedical field that needs to be clarified. Therefore, investigations of the physical and chemical details of small biological molecules interacting with MXenes, known as graphene-like new generation materials, will be the key to the development of applications in this field. In this thesis, we mainly focused on investigating the interaction between the selected two dimensional MXene materials, Ti3C2 and Ti2C, and the selected small organic molecules, dopamine, glycine, serine and glutamate in the atomic level by means of the first principles based density functional theory (DFT) calculations. In all structures the geometric optimizations were done and the electronic, magnetic and optical properties were discussed. As a result, we first verified the stability of structures by phonon dispersion curves and temperature dependent molecular dynamics calculations, and found that Ti3C2 and Ti2C can maintain their monolayer form at 300 K and 500 K temperatures for 2 ps. We observed the electronic structures and showed that Ti3C2 and Ti2C act as magnetic metals. In further step, we investigated the interaction of MXenes and selected organic molecules and found the orientations and points in which the binding energies have the maximum value. As a result, we found that dopamine bound to the Ti3C2 surface with the binding energy of 6.05 eV; while there is no chemical bonding but physical interaction between Ti2CF2 surface and dopamine, glutamate, glycine and serine molecules in the energy range of 0.504 and 0.743 eV.