The electrochemical stability of thiols on gold surfaces

Abstract

In this paper we present a comparative analysis of the electrochemical stability of alkanethiols, aromatic and heterocyclic thiols on the Au(111) and Au(100) faces in relation to the theoretical energetic data. The peak potential and surface coverage are used as the key parameters to estimate the electrochemical stability while work function changes, adsorption energies and surface free energies calculated from periodic DFT, including van der Waals interactions, are used for the theoretical estimation. We find that the peak potentials do not correlate with work function changes and adsorption energies in particular for aromatic and heterocyclic thiols. In contrast, the reductive desorption potentials for the different thiols show a good correlation with the surface free energy of the SAMs estimated by density functional theory calculations. Surface coverage is a key factor that controls reductive desorption through van der Waals interactions.

S‐S‐PEG‐COOH Self‐Assembled Monolayer on Gold Surface Enabled a Combined Assay for Serological EBV Antibody Isotypes

“…Compared with other traditional glass or silicon substrates, the behavior of SAMs of thiols on gold and silver has been widely used because of their stability and surface coverage. Gold and silver thin film nano‐islands coated on the porous glass substrate exhibited high‐performance enhancement in terms of optical sensitivity . S‐S‐PEG‐COOH reagent modified gold surface, forming a disulfide self‐assembled monolayer coupled with six PEG groups, and the incorporation of the PEG molecules reduces nonspecific adsorption .…”

Performances of the Lamb Model to Describe the Vibrations of Gold Quantum-Sized Clusters

“…SG and p-MBA ligands are fixed to the metallic cluster by Au-S covalent bonding to the gold core. The Au-S bond between ligand and core is stronger for the aliphatic SG than for the aromatic p-BMA 47 . In the former case, the ligandcore bond is thus more similar to the Au-Au bonding within the core.…”

Molecularly-tunable nanoelectrode arrays created by harnessing intermolecular interactions

“…Fig. 1A(b) shows selected examples of the combinations to create differences in terms of the binding strength (E * b , also see Table S1 †) based on density functional theory (DFT) calculations 25,26 in several recent reports, 27,28 which could also involve molecular packing as shown in our recent work. 25 These differences are harnessed by tuning the alkyl chain, aromatic moiety, and functional groups in terms of hydrophobic, guesthost, protonation, hydrogen-boding, or electrostatic interactions for a wide range of sensor applications.…”

“…It is the resulting difference in binding strength that constitutes the basis for manipulation of their intermolecular interactions and phase structures for the selective desorption by controlling the E * b , which determines the desorption peak potential (E p ). 28,[33][34][35] The basis for the selective reductive desorption is that E p depends on the molecular structure, chain length, and functional groups. For example, the potential shis negatively by $20 mV per (-CH 2 ) group for n-alkanethiolate monolayers at annealed gold.…”