The electronic, elastic and thermodynamic properties of carbon-and nitrogen-doped Hf₂PB: a theoretical approach

New boride MAX phase materials are more and more attractive because of their ability to absorb neutrons as compared to carbide and nitride MAX phases except for the excellent properties of both metal and ceramics. Hf₂PB was energetically, mechanically and dynamically stable, except for low elastic modulus. The electronic, mechanical and thermodynamic properties of the Hf₂PB_1−xM_x (M = C, N; x = 0, 0.25, 0.5, 0.75, 1) were systematically studied. The results show that all Hf₂PB_1−xM_x solid solutions have good metallicity. Doping of carbon and nitrogen atoms can improve the mechanical properties of materials. When the doping concentration of N atoms was 75%, the maximum bulk modulus B, shear modulus G and Young's modulus E were maximized. The mechanical isotropy of the solid solutions decreased with increased C (N)-doping. The solid solutions have high Debye temperature, lattice thermal conductivity and melting points. The thermal conductivity increased with increasing doping concentration. Hf₂PB_1−xM_x can be used as high-temperature structural materials or nuclear industrial materials. (paper)