The Brazil international has been catching the eye with his performances at the Parc des Princes since making the switch from Roma back in 2013.
Barca were one of the teams linked with a move for the promising 22-year-old, who already has 17 caps for his country.
Emery has now confirmed there was interest from the Blaugrana over the summer but feels the player made the right decision to stick with the Ligue 1 champions.
"Barca asked in the summer, but he is thankful to PSG, who gave him the opportunity to play in a big club," the Spaniard told El Pais. "He might love to play for Barcelona, but he respects what PSG gave him. That said, he's a complete player.
"He is a top footballer. In addition to his technical qualities, he listens to instructions. He is very concentrated, does what you ask of him. He can still improve in terms of leadership."