The researchers achieved this tuneability by tinkering with the additives (dopants) they included in the base material, magnesium germanium oxide, to change its optical properties.
“We can incorporate these into our material to construct a complicated pattern so that different parts glow for different durations,” said Lijia Liu, a chemistry professor in Western’s Faculty of Science.
“That is our ultimate security. It will be very difficult to find something that can achieve that property.”
While micrometer-sized persistent luminescent materials are already currently available, Liu and colleagues have developed a nanosized version, which can be used to print highly detailed patterns. The particles they created glow more brightly and longer that existing materials.
The team’s work, published in the journal ACS Applied Nano Materials, was informed by data collected at the Canadian Light Source.
Lead author Yihong Liu, a Western PhD student in chemistry, said the beamlines used – Brockhouse, SGM, and IDEAS – enabled the team to better understand the interaction between the dopants and the base material, which is the key to the tunable afterglow.
“When you observe something unusual in the material made in the lab, you wonder why. The spectroscopy technologies at the Canadian Light Source are powerful tools to answer these questions,” she said.
