Co-doped perovskite nanocrystals for multiplexed anticounterfeiting applications

Abstract

Transition and lanthanide metal ion doping in colloidal perovskite nanocrystals results in efficient visible to near-infrared emission. Here, we explore the role of visible and near-infrared multi-emission pathways provided through Mn-doped and Yb–Mn co-doped perovskite nanocrystals within advanced photoluminescence-based security features. The features provide overt functionality through visible photoluminescence from the underlying Mn-dopants. Meanwhile, the Yb-dopants enable covert information to be concealed through their inherent near-infrared emission. These engineered printed patterns are assessed in terms of ambient, moisture, and thermal stability. Finally, the complexity of encryption is further enhanced by chemically engineering the host–dopant energy transfer processes through anion exchange reactions. This enables write and erase functions to be realised in these perovskite NC-based security features.