Soak potato slices in a large bowl of cold water for 15 minutes. Drain potatoes and pat dry.  Preheat air fryer to 375°F (190°C). Wipe bowl dry with paper towels; add oil, salt, and black pepper. Mix potatoes into oil mixture and gently toss to evenly coat. Coat air fryer basket with cooking oil spray. Add half the potato slices, side by side, to the air fryer basket. Cook potatoes until chips are tender and crispy, about 15 minutes. Carefully transfer chips from air fryer to a plate. Repeat cooking with the remaining slices.  Adjust seasoning, if desired, and serve immediately.