title: Oxidation of elemental gold in alcohol solutions.
abstract: Gold is designated as the noblest metal because of its chemical inertness. It is known to dissolve in cyanide solutions in the presence of air or H2O2 or in halogen-containing solutions, aqua regia being the most famous example. Herein, we report a unique thiol, especially 4-pyridinethiol (4-PS), assisted dissolution of Au in alcohol solutions. Although dissolution was found to be very selective for pyridinethiols, such a phenomenon is astonishing since thiols are commonly used as etch resists for Au and even 4-PS is extensively used as a surface modifier for Au. To gain further understanding of the dissolution process, the influence of the reaction conditions was extensively studied. On the basis of the obtained results, a mechanism for the dissolution reaction is proposed. Fascinatingly, by tuning of the reaction conditions, this phenomenon can be applied in selective preparation of self-supporting nanometer-thick Au foils.
authors: Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, Helsinki, Finland.
authors: Minna T
authors: MT
authors: Räisänen
authors: Marianna
authors: M
authors: Kemell
authors: Markku
authors: M
authors: Leskelä
authors: Timo
authors: T
authors: Repo
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D007536:Isomerism; D007700:Kinetics; D015394:Molecular Structure; D050607:Organogold Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D010084:Oxidation-Reduction; D011725:Pyridines / Q000737:chemistry*; D012995:Solubility; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors
chemical_list: D000438:Alcohols; D050607:Organogold Compounds; D011725:Pyridines; D012996:Solutions; C042861:4-thiopyridine; D006046:Gold