Biluminescence Under Ambient Conditions: Water‐Soluble Organic Emitter in High‐Oxygen‐Barrier Polymer

Biluminescent organic systems displaying fluorescence and phosphorescence at room temperature under aerated atmosphere still remain uncommon to date. Especially the utilization of the room temperature phosphorescence (RTP) is limited, as it is effectively quenched by oxygen, rendering it incompatible with many applications for use in ambient conditions. So far, only encapsulation to prevent oxygen penetration into the films or the use of special steroid hosts are known concepts to allow conventional biluminescent emitters to show RTP. Here, the design and synthesis of a novel water‐soluble biluminescent emitter is reported. After dispersion in a host matrix, and using host/guest hydrogen‐bonding interactions, easy‐processable highly phosphorescent transparent thin‐films are realized. Their luminescent properties can be activated at will under aerated atmosphere for several weeks without degradation of the system. The polymer (host) mixture can even be readily used for 3D printing, leading to a large range of accessible phosphorescent objects. A new water‐soluble biluminescent emitter showing remarkably stable long‐lived phosphorescence, up to several weeks, in air is presented. Its ability to dissolve in organic and aqueous media combined with thoughtfully chosen host:guest systems leads to a wide range of complementary and innovative applications from luminescent programmable tags to 3D printed phosphorescent objects.