When you are setting up a Linear Sweep Voltammetry (LSV) experiment to study the Oxygen Reduction Reaction (ORR) in a 0.1 M KOH electrolyte, choosing the right potential range is crucial to get clear and useful results.

Here’s a general guideline:

1. Avoid Interference from Hydrogen Evolution: In alkaline solutions like 0.1 M KOH, hydrogen gas starts forming at more negative potentials (below about -0.6 V vs. RHE). It’s best to stay away from this region to keep your ORR data clean.

2. Stay Clear of Oxygen Evolution: On the positive side, oxygen evolution can kick in at potentials higher than +0.6 V vs. RHE. This could mess with your ORR readings, so it’s good to avoid going too positive.

3. Focus on the ORR Window: The ORR usually happens between +0.2 V and -0.4 V vs. RHE in alkaline media. This is the sweet spot where you’ll see the most relevant activity.

So, a good potential window for your LSV experiment in 0.1 M KOH would be from about -0.8 V to +0.2 V vs. RHE. This range should capture the key ORR behaviour while minimising interference from other reactions. You might need to tweak this slightly depending on your specific setup, but this range is a solid starting point.

thank you, i am using Ag/AgCl reference electrode. please can you mention the potential window according to that. after getting that data, i will convert the potential into RHE.

When you are using an Ag/AgCl reference electrode in 0.1 M KOH, you'll need to adjust the potential window to account for the difference between the Ag/AgCl electrode and the Reversible Hydrogen Electrode (RHE).

Conversion between Ag/AgCl and RHE:

To convert potentials from Ag/AgCl to RHE in 0.1 M KOH (which has a pH of about 13), you can use the following rule of thumb:

• Add approximately 0.964 V to the potential measured against Ag/AgCl to get the equivalent potential vs. RHE.

Suggested Potential Window for ORR:

Given that the typical ORR window vs. RHE is from -0.8 V to +0.2 V, the corresponding potential window vs. Ag/AgCl would be:

• Lower Limit: around -1.8 V vs. Ag/AgCl
• Upper Limit: around -0.75 V vs. Ag/AgCl

Final Potential Window:

So, the recommended potential window for your LSV experiment using an Ag/AgCl reference electrode in 0.1 M KOH would be:

• Potential Range: from -1.8 V to -0.75 V vs. Ag/AgCl

This range should allow you to capture the ORR without significant interference from hydrogen or oxygen evolution. After your measurements, you can convert the potentials back to RHE using the 0.964 V adjustment for easier comparison with other data.