Herein we show the effect of heat treatment of two dimensional layered titanium carbide structure (Ti 3 C 2 T x ), so called MXene. As prepared MXene has functional groups -OH, -F, -Cl. In order to remove the functional groups we heat treated the MXene in Ar (with 0.01% O 2 ) and H 2 (with 0.01% H 2 O) atmospheres. We discovered the significant decrease in the amount of functional groups (-F and -Cl) and increase in the -O content, which refers to the oxidation of the material. Also we determined the optimal regime for Raman spectroscopy in order to avoid any changes in the structure of the material. We revealed that titanium carbide changes its structure at 700 °C and 900 °C into two different titanium dioxide modifications like rutile and anatase in Ar (with 0.01% O 2 ) atmosphere. Also there are small changes occurred in Ti 3 C 2 Tx structure and formation of amorphous carbon after 700 °C treatment in H 2 (with 0.01% H 2 O) atmosphere and formation of TiO 2 (rutile) at 900 °C. Energydispersive X-ray spectroscopy (EDX) revealed the reduction of functional groups at 700 °C in both atmospheres and total disappearance of -F and -Cl and increasing the oxygen at 900 °C. The huge increase of oxygen by atomic percent, can be explained by the initial oxygen content in argon and hydrogen gases.

A chemical model of electron-dust plasmas consisting of electrons and dust particles is systematically developed. An insight is exploited that a single dust particle forms a potential well for electrons, whose depth is determined by the work function of the dust material. The whole electron fluid, initially concentrated inside the dust particles, is somehow reallocated between the bulk of the dust matter and the ambient space available, which is then interpreted as thermionic emission. An expression is employed for the Helmholtz free energy of the system, which includes the ideal and excess parts to thoroughly deal with interactions between the dusty plasma constituents. Numerical calculations of dust particle charge are performed in quite a broad domain of plasma parameters, and a straightforward comparison is made with the orbital motion limited (OML) approximation to demonstrate that the proposed calculation scheme predicts higher positive charge values of dust grains. It is also proved that the OML approximation exactly corresponds to the ideal-gas model when interactions between plasma particles are entirely neglected.

A pseudopotential model of intergrain interaction in dusty plasmas is proposed to take into account both the electrostatic polarization and the screening phenomena. The derivation is entirely based on the renormalization theory of plasma particles interaction developed previously. Dust particles are assumed to be conductive such that the polarization phenomenon can strictly be treated in the charge-image approximation. Such an assumption imposes no restraint on generality of the present consideration because the polarization effects are essential for accurate description of intergrain interaction potential. The pseudopotential model is then used in the hypernetted chain approximation (HNC) for the dust component to obtain the radial distribution function which reveals the non-monotonic behavior at sufficiently large values of the dust coupling parameter. This can be viewed upon as a short-or even long-range order formation in the dust component of the plasma.

The main goal of this report is to obtain the macropotentials of dusty plasma particles interactions which account for the collective events in the medium and, then, to analyze their dependence on plasma parameters. It is shown that the attraction between conductive dust grains turns possible due to the polarization phenomenon.

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