Electrodeposition of polyaromatic thin films for enhanced CO2R electrocatalyst longevity

Background and motivation 

Physical properties of the electrode are critical to their catalytic performance in electrolyzers and fuel cells. For instance, ionomer coatings that improve ionic couplings are mandatory to ensure good performance in fuel cells, while for CO2 reduction these coatings are being extensively investigated to counter the competitive hydrogen evolution reaction.

While most examples rely on brush-coated or adsorbed perfluorinated polymers such as teflon, an alternative strategy relying on the chemical bonding of the coating to the catalyst surface should theoretically ensure higher long-term stability of the coating (no peeling) while providing a strategy to phase out of the use of perfluorinated polymers. Within this strategy, polyphenylene-based coatings have recently been demonstrated to allow efficient and stable CO2 reduction on copper even in acidic environment. 

This master thesis intends in developing similar coatings on silver-based catalysts, and to use them to finetune the physical properties of the catalyst by the modification of the substitution on the phenylene backbone. The optimized coated catalysts will then be tested for CO2 reduction to demonstrate their improved catalytic activity.

Research objectives and methods

Based on precedents from the literature, polyphenylene-based coatings will be electrochemically deposited via the reduction of the available precursors. The substitution of the aromatic substrate will be systematically screened to assess its influence on the wettability and electrocatalytic activity of the electrode. Characterization techniques such as Raman, XPS an TOF-SIMS will be employed to assess the deposition, verify the thickness and homogeneity of the coating and influence of the deposition conditions on these characteristics. Conformal coating will be then applied on nanostructured electrode. The coated samples will then be compared to uncoated ones for CO2 reduction. Any observed effect on the stability and on the activity will be rationalized through the use of a toolkit of operando and post-mortem analyses previously used on bare catalysts within the group.
Finally, the optimized coating will be subjected to stress tests to determine its longevity and compare it with more conventional coatings.

Candidate profile

We are looking for a highly motivated student with a genuine interest for green energy applications and a background in electrochemistry. To ensure good integration within the team, a good level of oral and written English is compulsory. 
 

Type of Project: Thesis 

Master's degree: Master of Bioengineering; Master of Science; Master of Engineering Science 

Master program: Nanoscience & Nanotechnology 

Supervisor: Philippe Vereecken (Bioscience, Nano) 

For more information or application, please contact the supervising scientist Jerome Beaudelot (Jerome.Beaudelot@imec.be).