Miran, H.A., Altarawneh, M., Jaf, Z.N., Dlugogorski, B.Z. and Jiang, Z-T
الملخص الانجليزي
This contribution reports a comprehensive investigation into the structural, electronic and thermal
properties of bulk and surface terbium dioxide (TbO2); a material that enjoys wide spectra of catalytic
and optical applications. Our calculated lattice dimension of 5.36 Å agrees well with the corresponding
experimental value at 5.22 Å. Density of states configuration of the bulk structure exhibits a
semiconducting nature. Thermo-mechanical properties of bulk TbO2 were obtained based on the
quasi-harmonic approximation formalism. Heat capacities, thermal expansions and bulk modulus of
the bulk TbO2 were obtained under a wide range of temperatures and pressures. The dependency of
these properties on operational pressure is very evident. Cleaving bulk terbium dioxide affords six
distinct terminations. Bader’s charge distribution analysis for the bulk and the surfaces portrays an
ionic character for Tb-O bonds. In an analogy to the well-established finding pertinent to
stoichiometric CeO2 surfaces, the (111):Tb surface appears to be the thermodynamically most stable
configuration in the nearness of the lean-limit of the oxygen chemical potential. For the corresponding
non-stoichiometric structures, we find that, the (111):O+1VO surface is the most stable
configuration across all values of accessible oxygen chemical potentials. The presence of an oxygen
vacant site in this surface is expected to enable potent catalytic-assisted reactions, most notably
production of hydrogen from water.
حسين علي جان ميران | Hussein Ali Jan Miran | 3042