Phase formation of nanolaminated Mo2AuC and Mo2(Au1-xGax)2C by a substitutional reaction within Au-capped Mo2GaC and Mo2Ga2C thin films

Chung-Chuan Lai; Hossein Fashandi; Jun Lu; Justinas Palisaitis; Per O Å Persson; Lars Hultman; Per Eklund; Johanna Rosen

doi:10.1039/c7nr03663a

Phase formation of nanolaminated Mo₂AuC and Mo₂(Au_1-xGa_x)₂C by a substitutional reaction within Au-capped Mo₂GaC and Mo₂Ga₂C thin films

Nanoscale. 2017 Nov 23;9(45):17681-17687. doi: 10.1039/c7nr03663a.

Authors

Chung-Chuan Lai¹, Hossein Fashandi, Jun Lu, Justinas Palisaitis, Per O Å Persson, Lars Hultman, Per Eklund, Johanna Rosen

Affiliation

¹ Thin Film Physics Division, Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden. chula@ifm.liu.se johro@ifm.liu.se.

PMID: 29119985
DOI: 10.1039/c7nr03663a

Abstract

Au-containing nanolaminated carbides Mo₂AuC and Mo₂(Au_1-xGa_x)₂C were synthesized by a thermally induced substitutional reaction in Mo₂GaC and Mo₂Ga₂C, respectively. The Au substitution of the Ga layers in the structures was observed using cross-sectional high-resolution scanning transmission electron microscopy. Expansion of c lattice parameters was also observed in the Au-containing phases compared to the original phases. Energy dispersive spectroscopy detected residual Ga in Au-substituted layers of both phases with a peculiar Ga in-plane ordering for Au : Ga = 9 : 1 ratio along the Au-Ga layers in Mo₂(Au_1-xGa_x)₂C. These results indicate a generalization of the Au substitution reaction for the A elements in MAX phases.