Whisk together the lemon juice, maple syrup, vinegar, 1 tablespoon of oil and cayenne pepper in a shallow bowl or baking dish just large enough to hold the salmon fillets in a single layer. Add fillets to marinade, turning to coat on all sides. Marinate fillets at room temperature for 10 minutes, turning occasionally.
While salmon fillets are marinating, make a shallow aluminum foil tray, doubling the foil and folding up the edges. Place it on an rimmed baking sheet to make it easier to transfer to and from the broiler.
Preheat broiler. Transfer marinated fillets to a plate and season with salt and pepper. Reserve marinade and microwave it on high for 1 minute. Heat large nonstick skillet over medium-high heat. Add a tablespoon or so of oil, then place the fillets in the skillet flesh side down. Sauté for 3 minutes. Meanwhile, lightly coat your foil tray with more oil. Transfer fillets to foil tray, cooked side up. Brush fillets liberally with reserved marinade.
Transfer foil tray to broiler pan, sliding it from the baking sheet. Broil until fish is just cooked through, about 3 minutes. Use the baking sheet to remove foil tray from broiler. Sprinkle lemon zest over fillets and serve immediately.