A DFT Analysis of Butane Isomers Adsorption on Pt (001) and Pt (110) Surfaces: Role of vdW Interactions

ABSTRACT In this study, we present a comprehensive first‐principles investigation of the adsorption behavior of n ‐butane and iso ‐butane on Pt(001) and Pt(110) surfaces using various density functional theory (DFT) approaches. The computational methods employed include GGA‐based functionals (PBE, RPBE, and revPBE) as well as van der Waals‐inclusive functionals (vdW‐DF, vdW‐DF2, optPBE‐vdW, and BEEF‐vdW). Key bulk properties, cohesive energy, lattice parameter, and bulk modulus were systematically benchmarked against experimental data. Among the tested functionals, PBE provides the closest agreement with experiment for the lattice parameter and cohesive energy, whereas optPBE‐vdW most accurately reproduces the experimental bulk modulus. vdW‐DF2 predicts the lowest surface energy, indicating enhanced surface stability within this framework. Adsorption energies and structural features of adsorbate–surface systems are highly sensitive to the choice of exchange–correlation functional, with vdW‐inclusive functionals generally providing better agreement with adsorption energies measured by temperature‐programmed desorption (TPD). Projected density of states (PDOS) analyses indicate hybridization between the Pt 5d band and the C 2p orbital, as well as between the Pt 5d band and H 1 s orbitals.