No. Or at least, even if you can, it doesn't do what you want it to.
Note that there are no rules for gauntlets, so it's up to your DM whether gauntlets are weapons, or if they benefit your unarmed strikes in some way.
If gauntlets are weapons, then yes, you can use Magic Weapon or Psionic Weapon with them. But if they're weapons, then you don't get to use them to make unarmed strikes.
Alternatively, if gauntlets aren't weapons, and just benefit your unarmed strike, then you can't use Magic Weapon or Psionic Weapon on them anyway.
It's also worth pointing out that, if your DM doesn't consider gauntlets to be weapons, and doesn't let them benefit your unarmed strikes, then you could still, by RAW, use them as improvised weapons. In that case, they would not be able to benefit from Magic Weapon or Psionic Weapon, and you wouldn't be able to use them with unarmed strikes.
As a final note, if you can get your hands on some Demon Armor (credit to LinoFrankCiaralli for this suggestion), while you still won't be able to use Magic Weapon or Psionic Weapon on them, unarmed strikes made with the gauntlets count as magical, have a +1 bonus, and deal 1d8 damage instead of 1.