Article

Mechanism of electrochemical reduction of hydrogen peroxide on copper in acidic sulfate solutions.

Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Langmuir (Impact Factor: 4.19). 10/2007; 23(19):9911-8. DOI: 10.1021/la7013557
Source: PubMed

ABSTRACT Hydrogen peroxide is a commonly used oxidizer component in chemical mechanical planarization slurries, used in the processing of Cu metallization in microelectronics applications. We studied the electrochemical reduction of hydrogen peroxide on Cu in 0.1 M H2SO4 solutions using methods including cyclic voltammetry, rotating disk electrode experiments, surface-enhanced Raman spectroscopy, and density functional theory (DFT) calculations. The spectroscopy reveals that the hydrogen peroxide molecule is reduced at negative potentials to form a Cu-OH surface species in acidic solutions, a result consistent with the insight from Tafel slope measurements. DFT calculations support the instability of peroxide relative to the surface-coordinated hydroxide on both Cu(111) and Cu(100) surfaces.

0 Bookmarks
 · 
91 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study is to evaluate the electrochemical corrosion behaviour of Incoloy 800 in sulphate solutions containing H2O2 in the temperature range of 25–80 °C. The open circuit potential measurements, cathodic and anodic polarization and electrochemical impedance spectroscopy (EIS) were used to characterize the corrosion behaviour. The results provide kinetic data for reduction of hydrogen peroxide on Pt surface. The anodic polarization curves for Incoloy at different pH, temperature and H2O2 concentration are presented. EIS data generally confirm the polarization interpretations about the effects of various parameters. An equivalent circuit was used to fit all the acquired data.Research highlights► Kinetic data for electrochemical reduction of hydrogen peroxide is presented. ► Incoloy 800 polarization at various temperatures, pH and H2O2 concentration. ► EIS data generally confirms the polarization interpretations.
    Corrosion Science. 01/2010; 52(12):4035-4045.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Direct borohydride fuel cells (DBFC), which operate on sodium borohydride (NaBH4) as the fuel, and hydrogen peroxide (H2O2) as the oxidant, are receiving increasing attention. This is due to their promising use as power sources for space and underwater applications, where air is not available and gas storage poses obvious problems. One key factor to improve the performance of DBFCs concerns the type of separator used. Both anion- and cation-exchange membranes may be considered as potential separators for DBFC. In the present paper, the effect of the membrane type on the performance of laboratory NaBH4/H2O2 fuel cells using Pt electrodes is studied at room temperature. Two commercial ion-exchange membranes from Membranes International Inc., an anion-exchange membrane (AMI-7001S) and a cation-exchange membrane (CMI-7000S), are tested as ionic separators for the DBFC. The membranes are compared directly by the observation and analysis of the corresponding DBFC's performance. Cell polarization, power density, stability, and durability tests are used in the membranes' evaluation. Energy densities and specific capacities are estimated. Most tests conducted, clearly indicate a superior performance of the cation-exchange membranes over the anion-exchange membrane. The two membranes are also compared with several other previously tested commercial membranes. For long term cell operation, these membranes seem to outperform the stability of the benchmark Nafion membranes but further studies are still required to improve their instantaneous power load.
    Membranes. 01/2012; 2(3):478-92.
  • [Show abstract] [Hide abstract]
    ABSTRACT: A prussian blue (PB) film has been deposited on the surface of platinum (Pt) coated n-type epitaxial silicon (Pt/n-n-Si) wafer. The electro-deposition of PB was achieved by a cyclic scan in a potential range of −0.2 to +0.60V (vs SCE) at 50 mV/s for 5 cycles in a solution containing 2.5 mM FeCl3, 2.5 mM K3Fe(CN)6, 0.1 M KCl and 0.1 M HCl with an illumination from 50 W bromine-tungsten lamp. The emphasis is laid on that this modified silicon electrode can be used as a sensor for the photocurrent determination of hydrogen peroxide at a zero bias by a two-electrode system without reference electrode. The use of the PB modified Pt/n-n-Si electrode as a hydrogen peroxide sensor was demonstrated with good stability and selectivity. The PB film was characterized by cyclic voltammetry measurements and scanning electronic microscopy (SEM). A new photo-electrochemical sensor based on two-electrode system has been developed for determination of hydrogen peroxide.
    Integrated Ferroelectrics - INTEGR FERROELECTRICS. 01/2012; 135(1):110-118.

Similar Publications