Organic Light‐Emitting Diodes: Achieving Nearly 30% External Quantum Efficiency for Orange–Red Organic Light Emitting Diodes by Employing Thermally Activated Delayed Fluorescence Emitters Composed of 1, 8‐Naphthalimide‐Acridine Hybrids (Adv. Mater. 5/2018). Issue 5 (1st February 2018)