PhD Thesis Defence Presentations - Bjorn Hasa

Presentation Title (Τίτλος Παρουσίασης): Synthesis, characterization and study of innovative catalysts for low temperature galvanic and electrolytic elements
Presentation Type (Τύπος Παρουσίασης): PhD Thesis Defence Presentations
Speakers Full Name (Ονοματεπώνυμο): Bjorn Hasa
Speakers Affiliation (Προέλευση Ομιλητή): Department of Chemical Engineering, University of Patras
Seminar Room (Αίθουσα): Meeting Room
Event Date: Mon, Dec 10 2018, Time: 18:00 - 20:00
Abstract (Περίληψη)

The research conducted for this dissertation involves experiments in the field of electrochemistry and catalysis. Initially, a series of electrochemical reactions are conducted to examine our modified Pt-catalysts as well as the interaction of metal particles (Pt-Ru) with different carbon supporters. Then, those catalysts are studied as anodes electrodes of a membrane electrode assembly (MEA) during the operation of a PEM Fuel Cell or Electrolyzer. Additionally, the comparison of different substrates using Pt or Pt-Ni catalysts is evaluated by hydrogen evolution reaction (HER). Finally, the electrochemical promotion of catalysis (EPOC) is studied in an alkaline solution.

In the first chapter is described the modification of Pt-based anodic electrodes with different metals in order to have better activity during alcohol oxidation. The aim of this chapter is to understand the role of the modification of Pt with another metal (i.e. Ir or SnO2) and to explain the role of TiO2 in binary (Pt-TiO2) or ternary (Pt-Ru-TiO2) electrodes. 

In the second chapter the electrochemical experiments are carried out in a rotating disk electrode (RDE). The rotating disc electrode (RDE) is the classical hydrodynamic electroanalytical technique used to limit the diffusion layer thickness. Apart from the electrochemical and physicochemical methods, there is an extensive description of the catalysts preparation and carbon supporters. 

The third chapter is dedicated to a detailed description of fuel cell technology. The main categories of fuel cells and stacks components are briefly described. An extensive description of a PEM fuel cell operation using either hydrogen, methanol, or ethanol is shown. 

In the fourth chapter the electrochemical reforming of methanol and ethanol for hydrogen production using the catalysts of the first chapter is investigated. In this chapter hydrogen production methods as well as its storage and transport are described. The electrolysis process is carried out in a Polymer Electrode Membrane (PEM) electrolyzer. PEM is comprised of a Pt-Ru with modified TiO2 anode, a commercial Pt/C cathode, and a Nafion 117 electrolyte. 

In the fifth chapter, a series of Pt or Pt–Ni alloy catalysts on different substrates are synthesized by potentiostatic electrodeposition, and the optimum deposition parameters are determined by scanning electron microscopy (SEM). The effect of electrodeposition parameters on the morphology, composition, and electrocatalytic activity for Hydrogen Evolution Reaction (HER) is investigated. 

In the last chapter, we examine the effect of electrochemical promotion of catalysis (EPOC) on commercial M (M=Pt, Rh, Pd)/Vulcan XC72 (E-tek) electrodes in alkaline media. Various reactant mixtures (H2 and O2) are fed simultaneously through a glass frit to the anodic electrode. 


Speakers Short CV (Σύντομο Βιογραφικό Ομιλητή)

Bjorn Hasa

Tellou Agra 9, Patras, Greece


Research Experience

  • Electrochemical promotion of catalysis for hydrogen oxidation reaction in alkaline media using commercial catalysts Pt, Rh, and Pd.
  • Analyzing different metals such as Pt, Ru, Ti, Sn, Ir for hydrogen oxidation/evolution reaction (HOR/HER), oxygen reduction reaction (ORR), and alcohol oxidation reaction (AOR).

  • Examining the PEM Fuel Cell and PEM Electrolyzer Cell operations during alcohol feeding.

  • Collaborating with other research group to develop alternative analytical procedures for corrosion current and mass loss.

  • Testing graphene supporters for charge-discharge experiments for battery analysis.



Ph. D., Department of Chemical Engineering         2014-Present

University of Patras, Greece

M. S., Department of Physics                               2013

University of Patras, Greece

B. S., Department of Physics                                2011

University of Patras, Greece


Important Publications

  1. Bjorn Hasa, John Vakros, Alexandros Katsaounis. “Effect of TiO2 on Pt-Ru-based anodes for methanol electroreforming”, Applied Catalysis B: Environmental, 237, (2018) 811-816.
  2. Bjorn Hasa, Evangelos Kalamaras, Evangelos I. Papaioannou, John Vakros, Labrini Syggelou, Alexandros Katsaounis. “Effect of TiO2 Loading on Pt-Ru Catalysts During Alcohol Electrooxidation”, Electrochimica Acta, 179, (2015) 578-587.

  3. Bjorn Hasa, Evangelos Kalamaras, Evangelos I. Papaioannou, Labrini Syggelou, Alexandros Katsaounis. “Electrochemical Oxidation of Alcohols on Pt-TiO2 Binary Electrodes”, International Journal of Hydrogen Energy, 38, (2013) 15395-15404.