Bridging the Understanding between Oxygen Electrocatalysis Activity and Electrode Stability in Acidic Medium: An Approach Towards Designing Low-cost PEM Fuel cells and Water Electrolyzers (BOEESA_PEM-2021)

Korelacja między aktywnością katalizatora tlenowego a stabilizacją elektrod w środowisku kwasowym: Podejście do projektowania niskokosztowych ogniw paliwowych PEM i elektrolizerów wodnych


This project is focused to design Iron (Fe) or Nickel (Ni) containing Tantalum oxide (TaOx) and Hafnium oxide (HfOx) nanomaterials for efficient and stable oxygen electrocatalysis application. The desired nanostructured materials will be synthesized by electrochemical methods (i.e., by electrochemical anodization and electrodeposition). The morphology and elemental composition of the materials will be investigated by various sophisticated analytical and spectroscopic techniques; X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), Energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The oxygen electrocatalysis properties of the materials will be investigated in acidic electrolytes by employing a computer controlled potentiostat/galvanostat. The relationship between the catalytic activity and electrode stability will be established. We hope such a detailed study of designing highly active Fe/Ni-TaOx and Fe/Ni-HfOx materials and understanding their activity-stability issues will enrich our knowledge of acidic oxygen electrocatalysis. 

This research is part of the project No. 2021/43/P/ST5/02281 co-funded by the National Science Centre and the European Union Framework Programme for Research and Innovation Horizon 2020 under the Marie Skłodowska-Curie grant agreement no. 945339.

 

Principal Investigator: Biswaranjan Das Mohapatra


Project location

Faculty of Chemistry, Department of Physical Chemistry and Electrochemistry, Jagiellonian University
Gronostajowa 2, Krakow 30-387, Poland
www.chemia.uj.edu.pl (faculty website)
www.elektro.chemia.uj.edu.pl (group website) 


The scholarship holders working in the project will be students:

1. Izabela Darowska
2. Mateusz Szczerba

 

Project news

The nanoporous/nanotube structures of anodic TaOx, Fe-TaOx and HfOx has been optimized in fluoride ion containing H2SO4 /ethylene glycol electrolytes. The pore diameter and thickness of the doped and undoped oxide (TaOx and HfOx) layers was varied by controlling the anodization parameters (e.g., applied potential, anodization time, composition of electrolyte and temperature of electrolyte). The effect of annealing conditions (400-600 °C, air atmosphere) of the anodic oxide materials on their crystallinity and O2 electrocatalysis (O2 reduction and evolution reaction) activity was evaluated. The percentage of H2O2 production and electron transfer number (n) during O2 reduction (ORR) were calculated for all the catalysts.

Apart from the anodic structures, TaOx and HfOx electrodeposited (potentiostatically) on graphite foil were investigated for oxygen electrocatalysis application. The depositions were carried out at -1.5 and -1.7 V vs. SCE for 120 seconds in 50 mM TaCl5 or HfCl4 + 1 M KCl + 0.5 M KNO3 bath. All TaOx and HfOx deposited samples were annealed in air atmosphere for 5 h in 300 °C to investigate the effect of annealing conditions on the oxide phases of the materials. The materials demonstrated cathodic current for O2 reduction at about 0.1 V vs. SCE. The cyclic voltammetry (CV) graph for TaOx/graphite showed O2 reduction current density of -1.1 mA cm-2 at -0.3 V and this value for HfOx/graphite catalyst was -1.35 mA cm-2. These results qualitatively demonstrate the electrocatalytic ORR activity of TaOx and HfOx deposited graphite materials in acidic electrolyte. Rotating ring disk electrode (RRDE) studies are under progress to quantitatively investigate the ORR activities of these materials.

 

Contact details

Principal Investigator’s contact details:
Biswaranjan Das Mohapatra, PhD
Assistant professor
Jagiellonian University, 
Department of Physical Chemistry and Electrochemistry
Gronostajowa 2, Krakow 30–387, Poland
E-mail: biswaranjan.mohapatra@uj.edu.pl 
Phone: +48 12 686 25 73 

Project Supervisor/mentor’s contact details:
Prof. dr. hab. Grzegorz Sulka
Jagiellonian University
Department of Physical Chemistry and Electrochemistry
Gronostajowa 2, 30–387 Krakow, Poland
E-mail: sulka@chemia.uj.edu.pl
Phone: +48 12 686 25 18