Ellen Sjöstrand
Project Year
Ellen

Transitioning to renewable energy resources is necessary to mitigate climate change. However, their fluctuating electricity generation, from hours to seasons, creates a demand for long-duration energy storage. One option is to use electrochemical liquid organic hydrogen carriers (eLOHCs), which chemically bind hydrogen that can be produced using renewable energy. They thus act as both a fuel and energy storage, providing a decoupled power and storage system that is practical to transport. The acetone/isopropanol (IPA) pair is an especially promising eLOHC, since it is low-cost, non-toxic and readily abundant. To enable efficient use of these chemicals for energy storage, catalyst development is essential. Until now, investigations have been limited mainly to platinum and platinum alloys in acidic electrolytes. The objective of this project was to expand the knowledge to different catalysts to enable fundamental understanding of the origins of activity and selectivity. The precious metals platinum (Pt), rhodium (Rh), ruthenium (Ru), gold (Au) and palladium (Pd) were screened in different IPA concentrations in 0.1M perchloric acid and 0.1M potassium hydroxide, using cyclic voltammetry (CV) while varying scan rates and rotation rates. A new or increased oxidation peak was observed in the CV of at least Pt, Rh, Pd and Ru in both acid and base with IPA. The overpotential increased along Rh < Pt <  Pd < Ru in acid. Furthermore, an increased activity was observed in base compared to acid for most of the tested metals, supporting the theory that OH facilitates IPA oxidation by adsorbing on the surface. Overall the results indicate that there are multiple metals that can catalyze IPA oxidation in acid, as well as base.

Major
Innovative and Sustainable Chemical Engineering
University
Chalmers University of Technology
Faculty Sponsor(s):
J. Tyler Mefford
Departments:
Chemical Engineering
Mentor(s):
Jaewon Lee