Chemical manipulations of nanoscale electron transfers

Gold deposition on pyrite and the common sulfide minerals: An STM/STS and SR-XPS study of surface reactions and Au nanoparticles

“…We suggested that the effects observed both in XPS and STS are mainly caused by temporal electric charging of the nanoparticles, which have small enough capacitance and are electrically isolated from the support (Mikhlin et al, 2006a). Concurrently, sulfur adsorbed on gold NPs may affect the interfacial electron transfer (Geng et al, 2005), including the electrochemical behaviour of Au NPs (Chen et al, 1998;Chen, 2004;Su and Girault, 2005) and the kinetics of gold deposition and dissolution. Interestingly, the smaller Au particles were observed on galena and pyrrhotite, which release hydrogen sulfide at much faster rates than chalcopyrite and pyrite.…”

Oxidation of arsenopyrite and deposition of gold on the oxidized surfaces: A scanning probe microscopy, tunneling spectroscopy and XPS study

“…There are a series of studies in which Coulomb blockade was revealed in electrochemical reactions (see Daniel and Astruc, 2004 for a review). In particular, Chen and co-workers (see Chen, 2004 and references herein) discovered a quantized capacitance charging of gold nanoparticles protected with a monolayer of organic sulfides in aqueous electrolytes containing hydrophobic anions. Hence, Coulomb blockade or other mechanisms behind the suppression of tunneling current should hinder both cathodic and anodic reactions on small particles, particularly the charge transfer steps of the growth and oxidative dissolution of gold.…”

Catalytically Active Gold: From Nanoparticles to Ultrathin Films

“…[73][74][75][76] Ligand-stabilized metal nanoclusters in the size range of 1-2 nanometers were found to exhibit well-pronounced quantum size behavior. 77 Ag nanoparticles have been shown theoretically to exhibit three novel, size-dependent vibrational features compared with the bulk 78 and experimentally to reveal a series of equidistant resonances near the Fermi level with a decreasing energy separation with increasing cluster size.…”