Modeling of photocatalytic and photoelectric devices on a macroscopic device level
Look,
I try to give you a broad answer.
If you want band gaps, you need electronic structure that means DFT!

If you do MD that means classical mechanics means no electronic structure no band gaps.

You want to have solvent effects for your, I presume large system, then DFT is costly, you would be left with QM/MM or sometimes called double resolution.

Reactive forcefields such as Reaxff use some valence bond theory to treat electronic structure which is low level of theory and can not be extended to inorganic compound unless it's parametrized.

Finally all these methods are highly approximate, but for engineering purposes everything is approximate.