The effect of bulk conversion into surface on physical properties of HfO2: First principle study

HfO2 is among the most widely used ceramic material at high temperatures and has a direct energy band gap, but its value is above the solar spectrum region. The conversion from bulk to a surface may bring the energy band gap down. Therefore, this article seeks to address the important structural, electronic and thermodynamics behavior of HfO2 through density functional theory. The surface (001) of bulk HfO2 for different thicknesses are analyzed through the FP-LAPW + lo scheme and performed in the WIEN2k package for the first time. The optimized lattice parameters and band gaps of bulk HfO2 concur well with the previously available results. Additionally, the thermodynamic behaviors of HfO2 (i.e. bulk modulus, coefficient of thermal expansion, Debye temperature, heat capacity and entropy) are calculated through a Quasi-harmonic Debye model fixed in the Gibbs2 code. The computed thermodynamic behaviors of bulk HfO2 of (001) surface with different thicknesses are well correlated with corresponding published results.