yes, it possible. if your photocatalysis is driven by Hydroxyl radicals more than other radicals.
EDTA - even though it will arrest positive holes, it can also promote H2O2 generation, which at a potential of +0.96 V will further generate hydroxyl radicals.
Article EDTA-enhanced photocatalytic oxygen reduction on K-doped g-C...
Ascorbic Acid - same reason as the above, but if your catalyst contains ferric or ferrous ions or any redox couple, AA will promote generation of Hydroxyl radicals.