Progress of Cryogenics and Isotopes Separation

CYCLIC VOLTAMMETRY AS A TOOL FOR MODEL TESTING – INVESTIGATION METHOD FOR NOBLE METAL CATALYST’S DURABILITY

Claudia Sisu*, Radu Dorin Andrei, Adriana Marinoiu, Claudia Sandru, Marius Constantinescu, Irina Petreanu, Elena Carcadea

National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Uzinei Street no. 4, P.O. Box Râureni 7, 240050, Râmnicu Vâlcea, Romania

ABSTRACT

Cyclic voltammetry (CV), one of the most useful technique to investigate the electrocatalytic behaviour, is applied to determine the stability and durability of three noble metal catalysts. The current response due to a potential sweep gives us an electrochemical spectrum of the electrode surface, with information regarding the solid-state redox transitions, active area and the electrode capacitance. The CV's graphs obtained are used to determine the number of moles that are reduced/oxidized at the electrode during the reaction; by taking into consideration the area under the curve of the voltammogram. There are several noble metal nanoparticles (e.g., Pt, Au, Pd, and Rh) supported on carbon materials that are usually used as catalyst for heterogeneous and electrochemical catalysis. The present work investigates the electrochemical behaviour, by cyclic voltammetry (CV) method of three different catalysts, namely: commercial 10% Pt/C, graphene oxide (GrO) and platinum deposed on graphene oxide (Pt/GrO). The activity and stability of prepared samples versus commercial catalyst was investigated by CV. The study compares also, the durability of the three catalytic materials after 200 cycles in the potential range from -0.35-1 V vs Ag/AgCl reference electrode.

Keywords: Voltammetry, graphene, noble catalyst, Pt/ graphene oxide catalyst