Hello. I am a graduate student conducting research on BiVO₄ photoelectrodes.

I have been forming a BiOI film on FTO glass through an electrodeposition method (-0.1 V vs. Ag/AgCl) and reacting it with VO(acac)₂ (450°C, 2°C/min, 2 hours).

As you can see in the pictures below, there seems to be no problem up to the electrodeposition process of the BiOI film, but after the reaction with VO(acac)₂, a large amount of material disappears, or droplet-like marks remain.

I am unable to speculate on what might be causing this issue, so I would like to seek the insights of more experienced researchers.