First-principles calculations were used to study the energetics of intrinsic defects in

Ti2AlC and the effect of N or O impurity atoms upon the generation of Al

vacancies. The insertion of impurity atoms lowered the vacancy formation energy

of the neighboring Al. The formation of Al vacancies was related to experimental

observations of growth of AlN or Al2O3 nanowires and nanofibers on the surface of

Ti2AlC. Since the growth of these nanostructures was controlled by the generation

and migration of intrinsic defects, it was proposed that a tunable method for the

synthesis of such nanostructures was feasible by controlling impurities.

First-Principles Investigation of Intrinsic Defects and (N, O) Impurity Atom

Stimulated Al Vacancy in Ti2AlC. T.Liao, J.Wang, Y.Zhou: Applied Physics

Letters, 2008, 93[26], 261911