First-principles study on the mechanical properties of M2CT2 (M = Ti, Zr, Hf; T = O, F, OH) MXenes

  • Yu-Chang Lu
  • Cui-Lan RenEmail author
  • Chang-Ying WangEmail author
  • Ya-Ru Yin
  • Han Han
  • Wei Zhang
  • Ping HuaiEmail author


Two-dimensional (2D) transition metal carbides known as MXenes belong to a new branch of 2D material family, and their fundamental properties vary with their compositions and surface functionalizations. In this study, the structural and ideal mechanical properties of M2C-type MXenes and their functionalized M2CT2 MXenes (M = Ti, Zr, Hf; T = O, F, OH) were systematically examined via first-principles methods. The stress–strain curves of the MXenes under homogenous biaxial and uniaxial tension are identified, and the fundamental quantities (e.g., Young’s modulus, in-plane stiffness, and Poisson’s ratio) are addressed. With significantly higher strength and extended critical strains, the M2CO2 MXenes exhibit optimal flexibility when compared with that of M2C, M2CF2, and M2C(OH)2. Additionally, Hf2CT2 exhibits optimal tensile performance under uniaxial or biaxial tension when compared to that of Ti2CT2 and Zr2CT2. The Young’s modulus, in-plane stiffness, and Poisson’s ratio of MXenes with different surface functionalization increase in a sequence corresponding to OH < F < O. Furthermore, the effects of vacancy on the mechanical properties of MXenes are further explored and indicate that vacancy can significantly weaken the tensile properties of MXenes that are considered. Moreover, vacancy also results in a certain anisotropy of stress along armchair and zigzag directions even under the biaxial tension condition.


MXenes Mechanical properties Vacancy First-principles study 



The authors acknowledge the TMSR Supercomputer Center, CAS and the Shanghai supercomputer center for providing the computing resources.

Supplementary material

41365_2019_688_MOESM1_ESM.docx (569 kb)
Supplementary material 1 (DOCX 569 kb)


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Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghaiChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.Key Laboratory of Interfacial Physics and TechnologyChinese Academy of SciencesShanghaiChina
  4. 4.Changzhou Institute of TechnologyChangzhouChina
  5. 5.Center of Shanghai Light SourceShanghai Advanced Research InstituteShanghaiChina
  6. 6.School of Physical Science and TechnologyShanghaiTech UniversityShanghaiChina

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