Preheat the air fryer to 400°F (200°C) for 5 minutes.
In a medium bowl, toss the sweet potato cubes with 1/2 teaspoon olive oil, smoked paprika, garlic powder, 1/4 teaspoon salt, and 1/8 teaspoon black pepper until evenly coated.
Place the sweet potatoes in the air fryer basket in a single layer. Cook for 10 minutes, shaking the basket halfway through cooking.
While the sweet potatoes cook, pat the salmon fillets dry with paper towels. Brush each fillet with the remaining 1/2 tablespoon olive oil and season with the remaining 1/4 teaspoon salt and 1/8 teaspoon black pepper.
After the sweet potatoes have cooked for 10 minutes, carefully move them to one side of the air fryer basket. Place the salmon fillets skin-side down on the other side of the basket.
Continue cooking for 10 minutes, or until the salmon is cooked through and flakes easily with a fork, and the sweet potatoes are tender and crispy on the edges.
Remove the salmon and sweet potatoes from the air fryer. Serve immediately with lemon wedges for squeezing over the salmon.