Working in batches, add scallops to skillet in single layer; sauté until brown on outside and just opaque in center, about 2 minutes per side.
Transfer scallops to plate, leaving drippings in pan.
Add garlic and remaining sesame oil to drippings in skillet; stir 30 seconds. Add ginger, orange juice, soy sauce and orange peel. Boil until sauce thickens to syrup, stirring frequently, about 2 minutes.
Pour sauce over scallops and serve.