The Ligue 1 giants twice came from behind in the opening leg of the tie at the Parc des Princes on Tuesday night to peg Barca to a 2-2 draw.
Brazil international Moura was impressed by PSG's character in that encounter and feels a win is not beyond them at Camp Nou next week.
He told ESPN Brasil: "They are the favourites but we no doubt had a good game. We attacked them and showed courage.
"We were able to draw the game and I think we have the chance to get an even better result next week."
The 20-year-old, who joined PSG from native side Sao Paulo in January, is enjoying the chance to go up against European heavyweights like Barca so early in his career.
"It was a privilege to play against one of the best teams in the world," he added.
"It's an honor to play in the Champions League against a team like Barcelona despite the fact I'm so young."