LAUSR

Abstract Self-assembled monolayers (SAMs) of N-heterocyclic carbene (NHC) are built up on gold substrate. Electrochemical impedance spectroscopy (EIS) tests show that the NHC-based SAMs exhibit high stability under ultrasonic circumstance, over 90% of NHC molecules being retained at gold surfaces after ultrasonic treatment of 10 min in water. Computations of density functional theory (DFT) demonstrate the preferential adsorption of NHC molecules at atop sites of Au (1 1 1) plane, and the strong interaction between NHC molecules and Au surfaces is attributed to the bonding between 2-position C atoms and Au atoms by the hybridization of the C 2p orbitals with the Au 5d and 6s orbitals.