Mechanoluminescence Rebrightening the Prospects of Stress Sensing: A Review

Abstract

Mechanoluminescence (ML) is the emission of light when a solid material is subjected to stress. [8][9] The intensity of the ML shows a strong correlation with the applied stress, making it suitable for stress sensing. ML stress sensing is based on a unique transduction principle from stress to photons, which paves the way for advanced stress sensing. In particular, ML-based sensing shows significant advantages of distributed detection and remote response to an applied stress by virtue of photon transmission through space. In addition, excellent stretchability, biocompatibility, and self-powering ability can be achieved within the stress-tophoton transduction units since electronic conduction is not needed. Importantly, ML-based sensing enables compensation of the shortcomings of conventional sensing technologies for emerging applications. Considering the many extraordinary performance characteristics, ML may hopefully rebrighten the prospects of stress sensing.Over the past few decades, ML materials and ML-based stress sensing have been extensively studied. Great efforts have been made to develop a large number of ML materials, deeply understand the ML mechanism, and boost the potential for stress sensing applications. Several review papers have been devoted to ML and its applications. [10][11][12][13][14][15][16][17] Bunzil and Wong summarized ML materials and stress sensors based on lanthanide compounds. [10] Xie and Li surveyed the progress in ML compounds with a focus on fractoluminescence. [11] An overview of inorganic ML compounds was presented by Feng and Smet, which particularly provides deep insight into the crystal structures and their relation to ML. [12] Additionally, Zhang et al. reviewed inorganic ML compounds, concentrating on their compositions, preparation, characterizations, mechanisms, and applications. [13] However, compared with materials and mechanisms, less attention has been paid to the technical performance of ML-based stress sensing and its relevance to applications. Obviously, reasonable analyses of the up-to-date performance are beneficial for properly assessing the potential for future applications.In this paper, we start with a brief overview of the desired performance characteristics of advanced stress sensing for several new applications (Section 2). The state-of-arts and challenges are highlighted. In Section 3, ML materials, ML-based sensors, and technical features will be discussed in an attempt to comprehensively evaluate ML-based sensing technology andThe emergence of new applications, such as in artificial intelligence, the internet of things, and biotechnology, has driven the evolution of stress sensing technology. For these emerging applications, stretchability, remoteness, stress distribution, a multimodal nature, and biocompatibility are important performance characteristics of stress sensors. Mechanoluminescence (ML)-based stress sensing has attracted widespread attention because of its characteristics of remoteness and having a distributed response to mechanical stimuli...

Self‐Powered Interactive Fiber Electronics with Visual–Digital Synergies

“…[21] This causes the shallow electrons to be excited to conduction band (detrapping) and accelerated toward Cu 2+ luminescence acceptor, thereby radiating 510 nm, 2.5 eV green light. [22] In addition to the piezo-ML effect based on stress transfer in sheath composites itself, surface charge polarization caused by sliding friction will also cause the tribo-ML effect (Figure S16, Supporting Information). The interfacial triboelectric electric field causes the ZnS energy band to tilt further, and more electrons will be excited and fall back to luminescence acceptor (Figure 3d).…”

Time‐Resolved Bright Red to Cyan Color Tunable Mechanoluminescence from CaZnOS: Bi3+, Mn2+ for Anti‐Counterfeiting Device and Stress Sensor

“…[ 24,25 ] However, it is still a great challenge to manipulate the ML emission color through co‐doping with two or more activator ions. [ 26,27 ]…”

Effective Repeatable Mechanoluminescence in Heterostructured Li1−xNaxNbO3: Pr3+

“…[29] Therefore, combined with the piezoelectricity of the material, we believe that the applied stress can lead to the piezoelectric field, which causes the phenomenon of light emission under compressive load. [37,38] The possible trap-controllable and self-recoverable mode ML processes of LN0.5: Pr 3+ materials are schematically illustrated in Figure S8 (Supporting Information). As shown in Figure S8a (Supporting Information), under the excitation of sunlight at ambient temperature, the electrons act as carriers are promoted to the conduction band (process ① in Figure S8a, Supporting Information), and then captured by the traps below the conduction band (process ②).…”