Multiple Color Emission of Mechanoluminescence and Photoluminescence from SrZnSO: Bi³⁺ for Multimode Anticounterfeiting

Abstract

Mechanoluminescence materials that emit light under mechanical stimulation have attracted widespread attention in sensing, anti-counterfeiting and imaging applications. In this study, a series of novel Sr1-xBixZnSO (0.001≤x≤0.1) samples were synthesized by the method of high temperature solid-state reaction. It is worth noting that the distortion degree of SrO3S3 octahedron was increased with increasing Bi 3+ concentration, and the color manipulated Sr1-xBixZnSO which can emit different photoluminescence (blue to dark blue and finally red) and mechanoluminescence (orange to red) colors are obtained. Moreover, the deep traps can stably store and provide electronic 2 supplement to shallow traps released under mechanical stimulated. Therefore, devices made of SrZnSO: Bi 3+ phosphor and polydimethylsiloxane (PDMS) can be used as thermomechano-opto three-mode anti-counterfeiting. The ML intensity is linear to the external load, can be utilized for stress sensing or imaging.

Ultrasound‐Induced Mechanoluminescence and Optical Thermometry Toward Stimulus‐Responsive Materials with Simultaneous Trigger Response and Read‐Out Functions

“…Furthermore, Er 3+ also regulates the trap density, which determines the intensity of ML. [ 39 ] Concentration quenching is a competitive process between the rate of depopulation of the active energy level, and the rate of carrier injection. The amount of injected carriers can be changed through changing the energy migration path.…”

Stress-Induced Photoluminescence Change of Monolayer Nanosheet Prepared by Delamination of Aurivillius-Phase Layered Perovskite

“…The photoluminescence properties of Bi 3+ -substituted phosphors are also influenced by mechanical stress such as compression, distortion, stretching, and bending. Indeed, several previous reports confirmed that the photoluminescence emission color of a Bi 3+ -substituted phosphor was drastically changed when the material was ground in a mortar or scratched with a pencil. − Although those MCL materials have great potential for application not only as a simple pressure sensors but also as detectors of internal stress or cracks in transparent materials in non-destructive inspection, manipulation of MCL materials is still challenging due to their low reversibility and the difficulty of correlating the MCL intensity with stress intensity. Moreover, the fragile nature of ceramics has greatly hampered developments in the MCL field using inorganic materials.…”

Improving the luminescence property of the novel yellow-emitting phosphor SrLa2Sc2O7:Bi3+ with charge compensators (Li+, Na+, K+) and its application in NUV-based white LEDs

“…The energy transfer gives rise to a concentration quenching effect, leading to a decrease in the PL intensity. Using the Blasse formula, the critical distance R c for energy transfer between Bi 3+ ions can be calculated and the mechanism of the concentration quenching can be described as: 33,34 where x c = 0.06 is the critical concentration, V = 682.375 Å 3 is the cell volume and N = 4 is the number of cations per unit cell of SLSO:Bi 3+ . The calculated R c is approximately 17.58 Å, much larger than the critical concentration of 5 Å for exchange interactions.…”

“…The energy transfer gives rise to a concentration quenching effect, leading to a decrease in the PL intensity. Using the Blasse formula, the critical distance R c for energy transfer between Bi 3+ ions can be calculated and the mechanism of the concentration quenching can be described as: 33,34…”