Electrified carbon/iodide interface for hybrid capacitors

Electrochemical capacitors are effective energy storage devices which provide high power output with long cycle life (charging/discharging for millions of times) – a unique advantage over modern batteries. To increase their competitiveness and sustainability, alternative designs without any risks of flammability and toxicity are desirable.

The Lise Meitner project focuses on investigating charge transfer at the carbon/iodide interface in green aqueous electrolytes and its application for the development of high energy hybrid electrochemical capacitors. In these devices, one electrode works battery-like (almost constant potential profile) and the other one capacitor-like, while the resulting hybrid capacitor exhibits symmetric charge/discharge characteristics similar to an electric double layer capacitor (EDLC). The advantage of hybrid capacitors is the use of safe, non-toxic, eco-friendly and highly conductive aqueous electrolytes with the benefit of introducing redox active species such as iodides in order to achieve a high capacity at one electrode.

We aim to use advanced electrochemical and physicochemical techniques for understanding the structural changes in the carbon matrix upon interaction with redox active species as well as designing new materials for enhanced charge storage at the EDL. A Master thesis project is currently available in this context. The knowledge obtained from these studies will help to develop new electrode and electrolyte materials for future hybrid capacitors with sustainable components.