*2.2. DFT Calculations of Mo1íxPbxS2 Solid Solutions and Pby/MoS2 Intercalates*

The experimental work has indicated a time-dependent content of Pb in the samples of MoS2 nanotubes after Pb-promoted synthesis, which suggests that the MoS2 lattice forms an unfavorable environment for the Pb atoms in these nanostructures. In order to elucidate preliminary the accommodation type, chemical bonding and the highest possible (at equilibrium) concentration of Pb atoms in the samples of MoS2 nanotubes a set of DFT calculations were performed. Two cases were considered: (1) the

lead atoms substitute the Mo in the lattice and serve as dopants (Mo1í*x*Pb*x*S2 solid solutions); (2) the
