Co-Mo and Co-Mo-C Alloys Deposited in a Magnetic Field of High Intensity and their Electrocatalytic Properties

Abstract

The article presents results of tests on electrodeposition in a magnetic field of Co-Mo and Co-Mo-C alloys characterised by low overvoltage of hydrogen evolution. Addition of molybdenum and carbon was to lower the values of overvoltage of hydrogen evolution on cobalt. The influence of a magnetic field of high intensity (1 -12 T) on the deposits composition, structure and morphology was determined. The deposition was conducted in a magnetic field of parallel orientation of the magnetic field forces lines in relation to the working electrode. Electrocatalytic properties of the obtained alloy coatings within the range of hydrogen evolution were tested in a concentrated solution of NaOH. The obtained alloys were analysed with the XRD method, their composition was tested with the WDXRF technique and they underwent observation applying scanning electron microscopy (SEM). The comparison of electrocatalytic properties of Co-Mo alloys with properties of Co-Mo-C ones enabled determining the influence of carbon presence in cathodic deposits on the overvoltage value of hydrogen evolution on them.Keywords: hydrogen evolution, electrocatalytic properties, electrodeposition, Co-Mo alloys, Co-Mo-C alloys, magnetoelectrochemistry W artykule przedstawione zostały wyniki badań nad elektroosadzaniem w polu magnetycznym stopów Co-Mo oraz Co-Mo-C charakteryzujących się niskim nadnapięciem wydzielania wodoru. Dodatek molibdenu oraz węgla miałna celu obniżenie wartości nadnapięcia wydzielania wodoru na kobalcie. Określony zostałwpływ pola magnetycznego o wysokim natężeniu (1 -12 T) na skład, strukturę oraz morfologię osadów. Osadzanie prowadzone było w polu magnetycznym o równoległej orientacji linii siłpola magnetycznego względem elektrody pracującej. Właściwości elektrokatalityczne otrzymanych powłok stopowych w zakresie wydzielania wodoru badano w gorącym stężonym roztworze NaOH. Otrzymane stopy poddano analizie XRD, analizie składu z wykorzystaniem techniki WDXRF oraz obserwacjom z wykorzystaniem skaningowej mikroskopii elektronowej (SEM). Porównanie właściwości elektrokatalitycznych stopów Co-Mo z właściwościami stopów Co-Mo-C pozwoliło na określenie wpływu obecności węgla w osadach katodowych na wartość nadnapięcia wydzielania na nich wodoru.

Electrochemical Deposition of Ruthenium and Cobalt-Ruthenium Alloys From Acidic Chloride Ions Containing Baths

“…[1] The best catalytic properties are found in metals from the platinum group [2][3], but due to their high prices it is impossible to commercialise production of hydrogen as a common energy carrier. A solution to the problem can be application of alloy or composite catalysers of catalytic properties close to those of the platinum metals though much less expensive [4][5][6][7][8][9][10][11].…”

Research into influence of the electrolysis modes on the composition of galvanic Fe-Co-Mo coatings

“…Current density varied in the range of 7-25 mA/cm 2 at 90-100 °C. The amorphous coatings by the Co-Mo-C alloys were obtained by electrolytic deposition in the magnetic field [25]. The content of molybdenum in the alloys varies from 27.6 to 34.2 аt.…”

Electrodeposition of Co–Rh alloys from aqueous acidic chloride electrolytes

“…Due to high price of PGMs, a lot of attention is focused on a synthesis of their nanoparticles (Au [2,3], Pt [4]), nanofilms [5][6][7] and alloys [8][9][10][11] that being much cheaper can present close functional properties. It was demonstrated that also alloys of transition metals not containing PGMs, such as: Ni-Mo [12], Co-Mo [13], Co-Mo-C [13], Co-W [14], Co-W-C [14], Zr-Ni-Co [15] can be a very interesting group of materials because of their catalytic properties or ability to absorb hydrogen.…”