Density-functional theory studies of the calculation method for catalyst and the material’s energy barrier

Abstract

First-principles based density functional theory (DFT) is a total energy theory, which provides a wealth of understanding on the electronic structures of materials, with a reasonable computational cost, however has several limitations apart from its efficiency. It is the inaccuracy in the calculation of material’s band gap and size difference of computable theoretical size of nanoparticles and the size in experiments, which is one of the difficulties in catalyst calculation. To improve this, we used self-consistent hybrid DFT and Hubbard model to calculate structural and electrical characteristics of titanium dioxide, and compared the results with formal DFT and experimental results. Also, we developed improved cluster expansion model to investigate the CO2 reduction reaction of real size gold nanoparticle. We found out that improved model shows good agreement with formal experimental data. In addition, using the DFT theory, we investigate magnetocrystalline anisotropy energy of rare-earth free hard magnet and phase transition mechanism of PVDF.