M.Sc. Theophilus Kobina Sarpey

Courses and Dates

Offered Bachelor’s or Master’s Theses Topics

Exploring renewable energy systems with laser induced current transient thechnique

The advent of ultrafast lasers has paved the way and eased the investigations of mechanisms and phenomena, which hitherto were difficult to interrogate or measure. One of such mechanisms is the kinetics of the electrified electrode-electrolyte interface. The laser induced current transient (LICT) technique has proven to be a robust, unique, and indispensable tool for predicting to a high degree of accuracy the activity of reactions by identifying the so-called potential of maximum entropy (PME). The PME is the potential at the interface at which the degree of disorder peaks. At the PME, the reaction should proceed faster than at potentials remote from it. Thus, one can anticipate that the closer the PME is to the thermodynamic equilibrium potential of an electrocatalytic reaction, the faster the kinetics of this reaction should be. By employing the LICT technique, the PME measured at the electrode-electrolyte interface (i.e., Au polycrystalline electrode and Ar-saturated Na2SO4 electrolyte at a pH of 8) has been reported to be 0.58 V vs RHE. However, using Ar-saturated K2SO4 at the same pH yielded a PME value of 1.30 V vs RHE. Therefore, it is our considered view that this presents a stupendous opportunity to tailor the cation mixture of Na+ and K+ as electrolyte to obtain a PME value of 1.23 V vs RHE, the thermodynamic equilibrium potential of the oxygen reduction reaction (ORR). Hence, this presents the leeway for optimizing the activity towards the ORR via the tuning of the electrolyte cation concentration.

suitable as

• Master’s Thesis Condensed Matter Physics

Supervisor: Aliaksandr Bandarenka

Publications

See ORCID profile of Theophilus Kobina Sarpey as well.