Thesis work for Bachelor, Master or Diploma
An efficient energy storage solution is needed in order to increase flexibility of renewable energy sources and to improve integration of these sources into existing energy grids. Hydrogen is currently being investigated as one of the most promising options to achieve this feat. Using a unitized regenerative fuel cell, hydrogen can easily be generated using electrolysis mode and converted back to electricity in the same system using fuel cell mode. However, one of the biggest challenges remains the oxygen electrode, as both oxygen reduction (fuel cell) and oxygen evolution (electrolysis) are the rate determining reactions.
This work focuses on synthesis and characterization of bifunctional oxygen catalysts and their optimization in regard to their composition, comprising several active materials and catalyst support material.
During this work bifunctional oxygen catalysts with varying compositions shall be synthesized and characterized physically as well as electrochemically. This includes wet-chemical synthesis of catalyst nanoparticles and various annealing procedures. A series of tests should be conducted varying the ratio of both active components as well as the ratio of active component (combined) to support. Physical characterization should include for example XRD and BET surface area determination. Electrochemical measurements will be carried out using rotating disk electrode setup. Evaluation of catalysts should include bifunctionality, i.e. ratio of current at oxygen reduction and oxygen evolution as well as stability at fixed potentials and during frequent potential changes from one mode to the other.