The device, discovered Sunday outside the Colleyville woman's home, did not detonate. An affidavit says the box had two bowls taped together, a battery and powder.
Prosecutor Bret Helmer says Barouch failed to move on after the divorce and thought it would be better to put a bomb on his ex-spouse's porch.
Barouch was arrested Wednesday after alleged bomb-making materials were confiscated at his home. He went before a federal magistrate Thursday.
Defense attorney Matthew Belcher says there is good evidence that Barouch should be released.