title: Quantitative nuclear magnetic resonance for additives determination in an electrolytic nickel bath.
abstract: The use of proton nuclear magnetic resonance (¹H-NMR) for the quantitation of additives in a commercial electrolytic nickel bath (Supreme Plus Brilliant, Atotech formulation) is reported. A simple and quick method is described that needs only the separation of nickel ions by precipitation with NaOH. The four additives in the bath (A-5(2X), leveler; Supreme Plus Brightener (SPB); SA-1, leveler; NPA, wetting agent; all of them are commercial names from Atotech) can be quantified, whereas no other analytical methods have been found in the literature for SA-1 and NPA. Two calibration methods have been tried: integration of NMR signals with the use of a proper internal standard and partial least squares regression applied to the characteristic NMR peaks. The multivariate method was preferred because of accuracy and precision. Multivariate limits of detection of about 4 mL L⁻¹ A-5(2X), 0.4 mL L⁻¹ SPB, 0.2 mL L⁻¹ SA-1 and 0.6 mL L⁻¹ NPA were found. The dynamic ranges are suitable to follow the concentration of additives in the bath along electrodeposition. ¹H-NMR spectra provide evidence for SPB and SA-1 consumption (A-5(2X) and NPA keep unchanged along the process) and the growth of some products from SA-1 degradation can be followed. The method can, probably, be extended to other electrolytic nickel baths.
authors.affiliation: Departamento de Química Aplicada, Facultad de Química, Universidad del País Vasco, Apdo. 1072, San Sebastián 20080, Spain.
authors.forename: Miren
authors.initials: M
authors.lastname: Ostra
authors.forename: Carlos
authors.initials: C
authors.lastname: Ubide
authors.forename: Maider
authors.initials: M
authors.lastname: Vidal
mesh_terms: D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation; D009532:Nickel / Q000032:analysis*
chemical_list: D009532:Nickel