DFT and DFT-D3 Studies of Glycerol Adsorption on the Cu(111), Cu(100), and Cu(110) Surfaces

Adsorption of glycerol is the first step in many catalytic reactions to transform glycerol that was formed as biodiesel byproduct into valuable products. Among many feasible catalysts, Cu seems to be a good choice due to its abundance and cost consideration, though extensive studies are needed to evaluate the performance of Cu catalysts on glycerol transformation. Density functional theory (DFT) calculations and van der Waals corrected calculations (DFT-D3) were therefore performed in this work to study the adsorption of glycerol on the three most abundant copper surfaces: Cu(111), Cu(100), and Cu(110). Inclusion of the van der Waals interactions resulted in higher adsorption energies and shorter Cu-O bond distances. The most favorable adsorption location was determined to be the Cu(110) long bridge site. The strongest adsorption is the atop site on the Cu(111) and the hollow site on the Cu(100), though the other adsorption sites are also very favorable.