New Route for Stabilization of 1T-WS 2 and MoS 2 Phases

The phenomenon of a partial 2H→1T phase transition within multiwalled WS 2 nanotubes under substitutional rhenium doping is discovered by means of high-resolution transmission electron microscopy. Using density-functional tight-binding calculations for the related MoS 2 compound, we consider a possible origin of this phase transition, which was known formerly only for WS 2 and MoS 2 intercalated by alkali metals. An interplay between the stability of layered or nanotubular forms of 2H and 1T allotropes is found to be intimately related with their electronic structures and electro-donating ability of an impurity.