Nanoarchitectonics of Ln3+ (Eu3+/Tb3+)-induced polyelectrolyte aggregates (LIPAs) for multicolor luminescence in 3D-printed poly(Lactic acid)

Reversible bright-dark luminescence nanomaterials have been developed for information storage and anti-counterfeiting in recent years, however, their monochrome characteristic and 2D patterning impose limits on the effective information storage density. In this work, a new strategy for producing ultraviolet switchable and stable luminescent patterns is proposed, based on Ln3+ (Eu3+/Tb3+) induced-polyelectrolyte aggregates (LIPAs) with sharp multi-color optical properties. Under 365 nm excitation, a multicolor pattern can be observed using both red and green, which is not visible when this excitation light source is off. The LIPAs enable the luminescent lanthanide complexes to be compatibilized with poly(lactic acid) (PLA). Functional anti-counterfeiting patterns were prepared by 3D printing using luminescent PLA containing by Ln3+ (Eu3+/Tb3+) LIPAs. Invisible, adjustable and ultra-stable multicolor luminescent patterns well enable information storage and enhance information security for anti-counterfeiting applications.