Effects of Palladium(II) Chlorocomplex Speciation on the Controlled Interaction with a Polyaniline Film in Acid

Abstract

In this study, we determined the Pd(II) chlorocomplex species that has the most favorable interaction with an electropolymerized and protonated polyaniline (PANI) film. This study was completed with the intent to use this species to electrochemically build atomic palladium clusters in the PANI matrix. Varying amounts of NaCl were added to a KPdCl/HClO solution to result in three species studied: PdCl(HO), PdCl(HO), and PdCl. UV-vis spectroscopy was used to confirm the speciation, and Raman spectroscopy, X-ray photoelectron spectroscopy, and cyclic voltammograms were used to probe the interaction between the Pd species and PANI. It was determined that PdCl(HO) most effectively interacts with PANI as a result of the charge balance between the anion and the protonated nitrogen-containing groups in the polymer. It has been also found that some fraction of inserted Pd(II) cannot be reduced to Pd(0).

Metallo-Supramolecular Coordination Polymers Based on Amidopyridine Derivatives of Pillar[5]arene and Cu(II) and Pd(II) Cations: Synthesis and Recognition of Nitroaromatic Compounds

“…The band at 244 nm exhibited a bathochromic shift to 267 nm in the presence of Pd 2+ ions (Figure S17a) and to 257 nm in the presence of the Cu 2+ ions (Figures a and S16a). New bands appearing at 267 and 257 nm correspond to the formation of new 2 ·Cu 2+ or 2 ·Pd 2+ coordinate bonds, respectively …”

“…New bands appearing at 267 and 257 nm correspond to the formation of new 2•Cu 2+ or 2• Pd 2+ coordinate bonds, respectively. 37 The association constant of the complex 2•Cu 2+ was established by spectrophotometric titration at 257 nm in the range of the cation concentration from 2.5 to 90 μM and constant ligand concentration (10 μM). The logarithm of the association constant was equal to 4.91 (SI, Figure S16b).…”

Quantized Electrodes: Atomic Palladium and Gold in Polyaniline

“…[3,4] In that state the difference between "bulk" and "surface" atoms disappears and such atomic clusters may exhibit unusual catalytic properties. [5][6][7][8] Atomic metal clusters can be prepared using electrochemical techniques [9][10][11] or by utilizing mass-selective beam technology. [12][13][14] With the latter technique, a beam containing mixtures of atomic clusters is separated by mass and selected clusters are deposited on an inert, insulating substrate and characterized spectroscopically.…”

“…are adjusted in order to control the diminution to the final size. [9][10][11] The result is always governed by statistical distributions and the final sizes and their distribution varies. On the other hand, in the "bottom-up" procedure the atoms are assembled sequentially, one-by-one, [17] and in defined order.…”

“…In the former the usual experimental parameters, e. g. concentration, potential, time, etc. are adjusted in order to control the diminution to the final size [9–11] . The result is always governed by statistical distributions and the final sizes and their distribution varies.…”