Substituent Effects on the Adsorption of Dialkyl Sulfides on Gold Nanoparticles

Abstract
The adsorption of chloroethyl ethyl sulfide and 2,2‘-dichloro ethyl sulfide to gold nanoparticles has been examined in the gas phase using surface-plasmon resonance spectroscopy. The equilibrium constants for the gas-phase adsorption reactions are 14 ± 4 and 25 ± 5 atm-1, respectively. The bond energy of the Au−chloroethyl ethyl sulfide complex is 44 ± 9 kJ mol-1. The bond energy of Au−2,2‘-dichloro ethyl sulfide is estimated to be 47 kJ mol-1. Halogenation of the dialkyl side chains is found to have little impact on the chemistry, and only physisorption processes occur, analogous to dialkyl sulfide adsorption on Au surfaces.