New Route for Stabilization of 1T-WS₂ and MoS₂ Phases

The phenomenon of a partial 2H→1T phase transition within multiwalled WS2 nanotubes under substitutional rhenium doping is discovered by means of high-resolution transmission electron microscopy. Using density-functional tight-binding calculations for the related MoS2 compound, we consider a possible origin of this phase transition, which was known formerly only for WS2 and MoS2 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.