No. The tax returns are not related to work, policy or actions taken by the President, as President, or during his administration. It's not government-produced information or work product. Now, his NEXT tax return? That might be a different matter, but that probably falls outside of what is governed by the FOIA. If there was an investigation where that was reviewed as evidence of or refutation of allegations that he was enriching himself, or some other review, it (tax years while President) might become part of government information the public has a right to as part of information and evidence collected as part of a formal government investigation, but, barring that, it's his personal information, and probably does not fall under FOIA.
I'll try to add more links on the specifics of the law and what is covered, later, when I'm not at work. Keep in mind, my personal slant on FOIA is that almost nothing government-related should be exempt (most "national security" exemptions are really "I think the nation would be less secure if people knew we were violating laws"), but I don't see how, even with the broadest interpretation, this could be objectively gathered under that "umbrella."