Squeeze the artichoke heart halves gently to remove as much liquid as possible, then pat them dry with paper towels. This is key for a crispy coating.
Set up a breading station: flour in one shallow dish, beaten eggs in a second, and breadcrumbs mixed with parmesan, garlic powder, and black pepper in a third.
Dredge each artichoke heart in flour, dip in egg, then press into the parmesan breadcrumb mixture, coating all sides thoroughly.
Preheat the air fryer to 390F. Spray the basket with cooking spray and arrange the breaded artichoke hearts in a single layer. Spray the tops lightly with cooking spray. Air fry for 10-12 minutes, flipping once halfway, until golden brown and crunchy.
Serve immediately with warm marinara sauce for dipping and a squeeze of fresh lemon.