Researchers from Western University have developed a new technique to prevent forgeries of valuables — such as diplomas, currency, medications and artwork, for example — via an approach that offers several layers of anti-counterfeiting protection by making identifying markings significantly harder to forge.

To accomplish this, the team employed materials with a property called persistent luminescence (PersL).

Source: Western University/ACS Applied Nano Materials (2024). DOI: 10.1021/acsanm.4c01069

Distinguishing this luminescent material from current anti-counterfeiting tech that glows when it is exposed to ultraviolet (UV) light, but then stops glowing once the light source is removed, is that the inorganic phosphor nanoparticles will remain visible to the human eye for several minutes once the UV light source is removed.

Additionally, the new material produces a shade of red light that is difficult to reproduce. Further, an identification mark can be "programmed" to phase out, with some elements disappearing almost instantly, while other elements vanish after several minutes.

The researchers were able to achieve this by modifying the additives (dopants) included in the base material, magnesium germanium oxide, to alter its optical properties.

"We can incorporate these into our material to construct a complicated pattern so that different parts glow for different durations. That is our ultimate security. It will be very difficult to find something that can achieve that property," the researchers explained.

An article detailing the material, “Multiband MgGeO₃-Based Persistent Luminescent Nanophosphors for Dynamic and Multimodal Anticounterfeiting,” appears in the journal ACS Applied Nano Materials.

An accompanying video detailing the technology appears courtesy of Western University.