Manipulating the mechanical properties of Ti2C MXene: Effect of substitutional doping

Abstract

With the aim of manipulating the mechanical properties of the recently discussed two-dimensional material MXene, we investigate the effect of alloying. We consider substitutional doping of B and V at Ti and C sites of Ti 2 C. Calculations of quantities such as in-plane stiffness, Young's modulus, and critical strain through rigorous first-principles technique establish that B doping is highly effective in improving the elastic properties. Oxygen passivation of B-doped Ti 2 C in addition to improved elastic properties also exhibits reasonably high critical strains making them ideally suited for applications in flexible devices. Our study further reveals the presence of strong spin-phonon coupling in unpassivated Ti 2 C compounds which influences the mechanical behavior. The damage of Ti 2 C in its magnetic ground state of A-type antiferromagnetic structure is found to occur at much higher strain than that of the nonmagnetic Ti 2 C.

The Recent Advances in the Mechanical Properties of Self-Standing Two-Dimensional MXene-Based Nanostructures: Deep Insights into the Supercapacitor

“…The effect of doping on the elastic properties of MXenes was investigated by DFT calculations [ 51 ]. Specifically, B and V atoms were substitutionally doped into Ti and C sites in Ti 2 C, respectively, resulting in Ti 2 (C 0.5 B 0.5 ) and (Ti, V)C. While V-doping results only in marginal enhancement, B-doping yields improved the elastic properties by decreasing the in-plane Young’s modulus and the yield strength.…”

“…Specifically, B and V atoms were substitutionally doped into Ti and C sites in Ti 2 C, respectively, resulting in Ti 2 (C 0.5 B 0.5 ) and (Ti, V)C. While V-doping results only in marginal enhancement, B-doping yields improved the elastic properties by decreasing the in-plane Young’s modulus and the yield strength. The reduction in the stiffness can be attributed to the weak-bond of Ti-B compared to the Ti-C bond ( Figure 4 b,c) [ 51 ]. Figure 5 shows the calculated stress-strain curves using the non-magnetic (NM) and the lowest energy antiferromagnetic (AFM) states [ 51 ].…”

Probing the shear modulus of two-dimensional multiplanar nanostructures and heterostructures

“…With the feasible isolation of single layer carbon atoms, known as graphene [1,2], the fascinating and unprecedented properties of this monolayer nanostructure had initiated intense research in exploration of prospective alternative two-dimensional and quasi-two-dimensional materials that could possess exciting electronic, optical, thermal, chemical and mechanical characteristics [3][4][5][6][7][8][9]. It is important to investigate these materials at nano-scale as most of the interesting characteristics are in atomic scale and monolayer forms [10].…”

Thermochemical stability, and electronic and dielectric properties of Janus bismuth oxyhalide BiOX (X = Cl, Br, I) monolayers

“…More specically, the structural optimization calculations were performed until the maximal component of force on each atom and stress on the supercell volume of each slab system were close to the known optimum limits as reported previously for other 2D materials including TMDs or MXene and their heterostructures with graphene. 3,[60][61][62] For calculating the phonon density of states (DOS) on the pristine and Janus monolayers of bismuth oxyhalides, a minimum 4 Â 4 Â 1 supercell of the unit cell containing 6 atoms, i.e. a total of 96 atoms, and in-plane parameters $15-16 A, was sufficient for convergence.…”