A first-principles study of half-Heusler intermetallic compound MgAgAs with 2D-TiC/2D-Mo2TiC composite material

  • Ephraim Muriithi Kiarii
  • Krishna Kuben Govender
  • Messai Adenew Mamo
  • Penny Poomani GovenderEmail author
Regular Article


The world reliance on non-renewable and depleted energy resources has made the search for renewable and sustainable energy more significant. However, a theoretical study is necessary to give a more elaborate investigation of the electronic and optical properties since the role of the heterostructures is still deficient. Furthermore, no first-principles studies have been reported on 2D thermoelectric heterostructures comprising of MgAgAs, 2D-TiC and 2D-Mo2TiC material. Our calculated electronic results show no bandgap induction in the heterostructures compared to pure intermetallic MgAgAs, 2D-TiC and 2D-Mo2TiC material, which favours the separation and transfer of charge carriers and visible-light-driven activity. Based on the analysis of the electronic properties, band structure, projected density of state and spin-polarised contributions from the spin-down and spin-up eigenstates, the Mo2TiC–MgAgAs–Mo2TiC layer was found to have improved conductivity at the infrared region. This makes the electrons move easily from the surface of the thermoelectric material once generated and stored in the heterostructures. The proposed theoretical design offers a new way for the effective and large-scale fabrication of 2D-based thermoelectric materials for application in solar energy conversion and storage.


Density functional theory Electronic Intermetallic Optical Thermoelectric 



The authors would like to acknowledge the financial contributions from the Faculty of Science: University of Johannesburg, South Africa: Centre for Nanomaterials Science Research, Department of Applied Chemistry and the National Research Foundation (TTK14052167682). The authors are also grateful to the Centre for High-Performance Computing (CHPC) for computational resources provided.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Applied ChemistryUniversity of JohannesburgJohannesburgSouth Africa
  2. 2.Council for Scientific and Industrial Research, Meraka InstituteCentre for High-Performance ComputingCape TownSouth Africa

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