Electrodeposition of Cu-Ag Alloy Films at n-Si(001) and Polycrystalline Ru Substrates

Electrodeposition of Cu-Ag films from acidic sulfate bath was conducted at n-Si(001) and polycrystalline Ru substrates. Significant nucleation overpotential of 0.4 V is observed with the Cu-Ag bath at n-Si(001) substrate, whereas the electrodeposition of Cu-Ag at Ru substrate is influenced by Ru oxides at the surface. Incomplete coverage of Si substrate by Cu-Ag deposit was observed from the deposition systems without Ag(I), or with 0.1 mM Ag(I), comparing with the compact Cu-Ag film obtained with the deposition bath containing 0.01 mM Ag(I). Layered and faceted Cu-Ag deposit was observed at small Cu deposition overpotential with the Ru substrate. Phase composition of the Cu-Ag deposits at n-Si(001) substrate from electrolyte with various Ag(I) concentrations is examined by XRD. Limited solubility of Ag (0.4 at.%) was observed in fcc-Cu until phase separation occurs. The classical model for nucleation kinetics in electrodeposition was used to examine the potentiostatic transients of the Cu-Ag electrodeposition at n-Si(001) substrate.

Extraction of Cu(II) From Acidic Sulfate Media by Palm Kernel Fatty Acid Distillate: Stoichiometry and Thermodynamic Studies

In efforts to develop a novel low-cost and eco-friendly organic solvent, namely, palm kernel fatty acid distillate (PKFAD), with free fatty acids (FFAs) as the active components, for Cu(II) extraction from acidic sulfate media, this work aimed to gain insight into the stoichiometry of Cu(II)-FFA complexes (extracted species) in PKFAD and their extraction thermodynamics. The former was explored by both the equilibrium slope and numerical analyses, while the latter was determined from the extraction of Cu(II) by PKFAD at different temperatures. Both the equilibrium slope and numerical analyses revealed that the stoichiometry of Cu(II)-FFA complexes in PKFAD was 1:6, whereas the thermodynamic study indicated that Cu(II) extraction by PKFAD was exothermic, nonspontaneous, and enthalpy-driven over the temperature range studied. A plausible structure of Cu(II)-FFA complexes in PKFAD was also postulated based on the thermodynamic data obtained.

Quantitative relationship between the structures and properties of VOCs and the SOA formation on the surface of acidic aerosol particles

In this research, all the efforts, based on a series of molecular dynamics simulations on the interfacial process between VOC-contaminated air and the acidic sulfate, were made to find how...