title: A universal rule for organic ligand exchange.
abstract: Most synthetic routes to high-quality nanocrystals with tunable morphologies predominantly employ long hydro-carbon molecules as ligands, which are detrimental for electronic and catalytic applications. Here, a rule is found that the adsorption energy of an organic ligand is related to its carbon-chain length. Using the density functional theory method, the adsorption energies of some commonly used ligand molecules with different carbon-chain lengths are calculated, including carboxylate, hydroxyl, and amine molecules adsorbed on metal or metal oxide crystal surface. The results indicate that the adsorption energy of the ligand molecule with a long carbon chain is weaker than that of a smaller molecule with same functional group. This rule provides a theoretical support for a new kind of ligand exchange method in which large organic ligand molecules can be exchanged by small molecules with same functional group to improve the catalytic properties.
authors.affiliation: MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, State Key Laboratory for Mechanical Behavior of Materials, School of Science, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, P. R. China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: You
authors.forename: Wenjin
authors.initials: W
authors.lastname: Wang
authors.forename: Shengchun
authors.initials: S
authors.lastname: Yang
keywords: adsorption energy; catalytic property; density functional theory; length of carbon chain; surface treatment