The Vanadium Redox Reactions - Electrocatalysis versus Non-Electrocatalysis.

Area of Science:

• Electrochemistry
• Materials Science
• Surface Chemistry

Background:

• Literature suggests surface groups on porous carbon electrodes catalyze vanadium redox reactions (V(II)/V(III) and V(IV)/V(V)).
• Assessing the electrochemically active surface area (ECSA) on porous electrodes is challenging.

Purpose of the Study:

• To critically analyze existing literature on catalytic effects of surface groups on porous carbon electrodes for vanadium redox reactions.
• To present a novel method for determining the ECSA of porous electrodes.
• To re-evaluate the catalytic claims using the new ECSA assessment method.

Main Methods:

• Critical literature review.
• Development and application of a new method for assessing electrochemically active surface area on porous carbon electrodes.
• Electrochemical analysis of vanadium redox reactions.

Main Results:

• No catalytic effects of surface groups were substantiated for V(II)/V(III) and V(IV)/V(V) redox reactions when using the developed ECSA method.
• The study critically analyzes previous claims in relation to the group's own work.

Conclusions:

• The catalytic effects of surface groups on porous carbon electrodes for vanadium redox reactions are unsubstantiated by this study.
• Electrochemical potential and temperature are critical parameters for evaluating electrocatalysis.