Chemically Modified Electrodes: VIII . The Interaction of Aqueous with Native and Silanized Electrodes

Abstract

SnO2 electrodes in the form of thin, highly doped films on glass were exposed to aqueous RuCl3 solutions and examined electrochemically and by x-ray photoelectron spectroscopy (XPES). For both native SnO2 and SnO2 silanized with an alkylamine silane, the Ru is strongly chemisorbed and yields a broad chemically reversible surface wave near 0V and an irreversible oxidation wave near +0.85V. These are interpreted as Ru(II~-.IIl) and Ru(IlI--> IV) processes, respectively. XPES sputtering experiments reveal the existence oK suDsurmce Ru at depths similar to observed O/Sn nonstoichiometry.

XPS, UV–Vis, FTIR, and EXAFS Studies to Investigate the Binding Mechanism of N719 Dye onto Oxalic Acid Treated TiO2 and Its Implication on Photovoltaic Properties

“…The main feature of the O 1s XPS spectrum of N719 sensitized on OA-TiO 2 is the appearance of a new well-resolved peak at 529.5 eV and the disappearance of the peak corresponding to the O – at the WO-TiO 2 surface. The new peak at 529.5 eV is assigned to a Ru–O bond. , The origin of this new peak may be due to the substitution of an NCS group of the dye by O – of the oxalic acid. In addition, the disappearance of the O – peak could be due to large electron scattering arising from the presence of oxalate ions and the dye layer on the WO-TiO 2 surface.…”

“…The new peak at 529.5 eV is assigned to a Ru−O bond. 31,32 The origin of this new peak may be due to the substitution of an NCS group of the dye by O − of the oxalic acid. In addition, the disappearance of the O − peak could be due to large electron scattering arising from the presence of oxalate ions and the dye layer on the WO-TiO 2 surface.…”

“…The main feature of O 1s XPS spectrum of N719 sensitized on OA-TiO 2 is the appearance of new well resolved peak at 529.5eV and disappearance of peak corresponding to the Oat WO-TiO 2 surface. The new peak at 529.5eV is assigned to Ru-O bond [31][32] . The origin of this new peak may be due to the substitution of NCS group of the dye by Oof the oxalic acid.…”

Modification of a platinum electrode surface by irreversible adsorption of adenosine-5'-monophosphate and metallation by iron

“…For example, metallation of modified electrodes by ruthenium complexes via ligand exchange reactions has been reported (11, 12, [16][17][18][19]. Silanized Sn02 was metallated by Ru(III) chloride (20). Metallation of glassy carbon which was modified by covalent bonding of tetra(aminophenyl)porphyrin (21,22) by Mn, Fe, Co, Ni, Cu, and Zn was demonstrated (22).…”

Surface characterization

“…XPS was used to correlate ruthenium oxide surface composition with electrode electrochemical behavior (479). Chemisorption of Ru on Sn02 studied by XPS verifies penetration of Ru to the metal interface (582), and 02 chemisorption was also studied by EPR (102). RuO* has also been studied using the atom probe, a variant of FIM which employs a time-of-flight mass spectrometer (120).…”