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Mechanoluminescence (ML) sensing technologies open up new opportunities for intelligent sensors, self-powered displays and wearable devices. However, the emission efficiency of ML materials reported so far still fails to meet the growing application requirements due to the insufficiently understood mechano-to-photon conversion mechanism. Herein, we propose to quantify the ability of different phases to gain or lose electrons under friction (defined as triboelectric series), and reveal that the inorganic-organic interfacial triboelectricity is a key factor in determining the ML in inorganic-organic composites. A positive correlation between the difference in triboelectric series and the ML intensity is established in a series of composites, and a 20-fold increase in ML intensity is finally obtained by selecting an appropriate inorganic-organic combination. The interfacial triboelectricity-regulated ML is further demonstrated in multi-interface systems that include an inorganic phosphor-organic matrix and organic matrix-force applicator interfaces, and again confirmed by self-oxidization and reduction of emission centers under continuous mechanical stimulus. This work not only gives direct experimental evidences for the underlying mechanism of ML, but also provides guidelines for rationally designing high-efficiency ML materials. Mechanoluminescence enables sensing applications of mechanical stimuli. Here, the authors reveal the importance of interfacial triboelectricity to this phenomenon in inorganic-organic composite materials.

Persistent mechanoluminescence (ML) with long lifetime is highly required to break the limits of the transient emitting behavior under mechanics stimuli. However, the existing materials with persistent ML are completely trap‐controlled, and a pre‐irradiation is required, which severely hinders the practical applications. In this work, a novel type of ML, self‐charging persistent ML, is created by compositing the Sr3Al2O5Cl2:Dy3+ (SAOCD) powders into flexible polydimethylsiloxane (PDMS) matrix. With no need for any pre‐irradiation, the as‐fabricated SAOCD/PDMS elastomer could exhibit intense and persistent ML under mechanics stimuli directly, which greatly facilitates its applications in mechanics lighting, displaying, imaging, and visualization. By investigating the matrix effects as well as the thermoluminescence, cathodoluminescence, and triboelectricity properties, the interfacial triboelectrification‐induced electron bombardment processes are demonstrated to be responsible for the self‐charged energy in  SAOCD under mechanics stimuli. Based on the unique self‐charging processes, the SAOCD/PDMS further exhibits mechanics storage and visualized reading activities, which brings novel ideas and approaches to deal with the mechanics‐related problems in the fields of mechanical engineering, bioengineering, and artificial intelligence. Herein, a novel type of mechanoluminescence (ML), self‐charging persistent ML, is reported by compositing the Sr3Al2O5Cl2:Dy3+ powders into flexible polydimethylsiloxane matrix. In addition to facilitating the applications in mechanics displaying and visualization, the unique self‐charging processes endow the materials with mechanics storage and visualized reading activities, showing broad application prospects in mechanical engineering, bioengineering, and artificial intelligence.

Mechanoluminescence, a smart luminescence phenomenon in which light energy is directly produced by a mechanical force, has recently received significant attention because of its important applications in fields such as visible strain sensing and structural health monitoring. Up to present, hundreds of inorganic and organic mechanoluminescent smart materials have been discovered and studied. Among them, strontium‐aluminate‐based materials are an important class of inorganic mechanoluminescent materials for fundamental research and practical applications attributed to their extremely low force/pressure threshold of mechanoluminescence, efficient photoluminescence, persistent afterglow, and a relatively low synthesis cost. This paper presents a systematic and comprehensive review of strontium‐aluminate‐based luminescent materials’ mechanoluminescence phenomena, mechanisms, material synthesis techniques, and related applications. Besides of summarizing the early and the latest research on this material system, an outlook is provided on its environmental, energy issue and future applications in smart wearable devices, advanced energy‐saving lighting and displays. Mechanoluminescence materials have recently attracted significant research interest due to their enormous modern applications in energy, sensing, anti‐counterfeiting, wearable display, and sport science. Strontium‐aluminate‐based luminescent materials’ mechanoluminescence is reviewed on the phenomena, mechanisms, material synthesis techniques, and related application.

Mechanoluminescence (ML) is a phenomenon characterized by photon emission in response to mechanical stimulus. ML is usually observed in inorganic crystals that produce strain electric fields if deformed. After being doped with luminescent lanthanide and transition‐metal ions, ML can be significantly enhanced and rationally tuned, which leads to promising applications, such as light sources, displays, and advanced sensors to probe the dynamic stress distribution over a large area. This Minireview focuses on recent developments in the design and synthesis of doped ML phosphors, as well as highlighting state‐of‐the‐art applications of these phosphors. Phosphors under pressure: Mechanoluminescence (ML) is a phenomenon characterized by photon emission in response to mechanical stimulus. Recent research activities and progress in ML phosphors comprised of lanthanide or transition‐metal dopants are described. Challenges for future study are also discussed.

Lanthanides-doped luminescent materials have gathered considerable attention due to their application potential in stress sensing, lighting and display, anti-counterfeiting technology and so forth. However, existing materials mainly cover the 380–1540 nm range, with slight extension to the UV region, impeding their applications in solar-blind imaging, background-free tracking, concealed communication, etc. To address this challenge, here we propose guidelines for far-UVC (200–230 nm) optical design. Accordingly, we achieve multi-stimulated far-UVC luminescence at ~222 nm in Pr 3+ -doped SrF 2 , stemming from the inter-configurational 4f5d → 4f  2 transition of Pr 3+ . Besides Pr 3+ , the SrF 2 host shows high tolerance to Ce 3+ , Nd 3+ , Sm 3+ , Eu 2+,3+ , Gd 3+ , Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ , Tm 3+ and Yb 3+ , vastly extending the emission wavelength across the entire spectral range from 200 to 1700 nm. Particularly, these materials exhibit self-recoverable mechanoluminescence by direct mechanical excitation, along with thermally and mechanically stimulated emission after X-ray irradiation. We demonstrate that these lanthanides-doped SrF 2 crystals offer unique opportunities for high-contrast marking and structural health monitoring in complex environments. The authors propose a set of guidelines for far-UVC optical design, under which the multi-stimulated far-UVC luminescence at 222 nm in Pr 3+ -doped SrF 2 is realized, offering unique opportunities for solar-blind imaging and structural health monitoring in complex environments.

Flexible organic materials that exhibit dynamic ultralong room temperature phosphorescence (DURTP) via photoactivation have attracted increasing research interest for their fascinating functions of reversibly writing-reading-erasing graphic information in the form of a long afterglow. However, due to the existence of a nonnegligible activation threshold for the initial exposure dose, the display mode of these materials has thus far been limited to binary patterns. By resorting to halogen element doping of carbon dots (CDs) to enhance intersystem crossing and reduce the activation threshold, we were able to produce, for the first time, a transparent, flexible, and fully programmable DURTP composite film with a reliable grayscale display capacity. Examples of promising applications in UV photography and highly confidential steganography were constructed, partially demonstrating the broad future applications of this material as a programmable platform with a high optical information density.

Distinct types of luminescence that are activated by various stimuli in a single material offer exciting developmental opportunities for functional materials. A versatile sensing platform that exhibits photoluminescence (PL), persistent luminescence (PersL), and mechanoluminescence (ML) is introduced, which enables the sensitive detection of temperature, pressure, and force/stress. The developed Sr2MgSi2O7:Eu2+/Dy3+ material exhibits a linear relationship between ML intensity and force and can be used as an ML stress sensor. Additionally, the bandwidth of the PL emission band and the PL lifetime of this material are remarkably sensitive to temperature, with values of ≈0.05 nm K−1 and 1.29%/K, respectively. This study demonstrates PersL pressure sensing for the first time, using long‐lasting (seconds) lifetime as a manometric parameter. The developed material functions as an exceptionally sensitive triple‐mode visual pressure sensor; specifically, it exhibits: i) a sensitivity of ≈−297.4 cm GPa−1 (8.11 nm GPa−1) in bandshift mode, ii) a sensitivity of ≈272.7 cm−1/GPa (14.8 nm GPa−1) in bandwidth mode, and iii) a sensitivity of 42%GPa−1 in PL‐lifetime mode, which is the highest value reported to date. Notably, anti‐counterfeiting, night‐vision safety‐sign, 8‐bit optical‐coding, and QR‐code applications that exhibit intense PersL are demonstrated by 3D‐printing the studied material in combination with a polymer. A multifunctional sensing platform of temperature, pressure, and stress is built, which is based on three different types of luminescence, photo‐, persistent‐, and mechano‐luminescence. Combined with the 3D‐printing technique, it also has practical uses like anti‐counterfeiting, night‐vision safety‐sign, and 8‐bit optical‐coding and QR codes.

Mechanoluminescence is a smart light‐emitting phenomenon in which applied mechanical energy is directly converted into photon emissions. In particular, mechanoluminescent materials have shown considerable potential for applications in the fields of energy and sensing. This study thoroughly investigates the mechanoluminescence and long afterglow properties of singly doped and codoped Sr 2 MgSi 2 O 7 (SMSO) with varying concentrations of Eu 2+ and Dy 3+ ions. Subsequently, a comprehensive analysis of its multimode luminescence properties, including photoluminescence, mechanoluminescence, long afterglow, and X‐ray‐induced luminescence, is conducted. In addition, the density of states mapping is acquired through first‐principles calculations, confirming that the enhanced mechanoluminescence properties of SMSO primarily stem from the deep trap introduced by Dy 3+ . In contrast to traditional mixing with Polydimethylsiloxane, in this study, the powders are incorporated into optically transparent wood to produce a multiresponse with mechanoluminescence, long afterglow, and X‐ray‐excited luminescence. This structure is achieved by pretreating natural wood, eliminating lignin, and subsequently modifying the wood to overall modification using various smart phosphors and epoxy resin composites. After natural drying, a multifunctional composite wood structure with diverse luminescence properties is obtained. Owing to its environmental friendliness, sustainability, self‐power, and cost‐effectiveness, this smart mechanoluminescence wood is anticipated to find extensive applications in construction materials and energy‐efficient displays.

The quest for mechanoluminescence (ML) in zinc sulfide (ZnS) spans more than a century, initially sparked by observations of natural minerals. There has been a resurgence in research into ML materials in recent decades, driven by advances in optoelectronic technologies and a deeper understanding of their luminescent properties under mechanical stress. ZnS, in particular, has garnered attention owing to its remarkable ability to sustain luminescence after more than 100,000 mechanical stimulations, positioning it as a standout candidate for optoelectronic applications. In contrast to conventional photoluminescent and electroluminescent light sources, ZnS composite elastomers have emerged as flexible, stretchable self‐powered light sources with considerable practical implications. This review introduces the development history, ML mechanisms, prototype ML devices, ZnS‐based ML material preparation methods, and their diverse applications spanning environmental mechanical‐to‐optical energy conversion, E‐signatures, anti‐counterfeiting, wearable information sensing devices, advanced battery‐free displays, biomedical imaging, and optical fiber sensors for human–computer interactions, among others. By integrating insights from ML‐optics, mechanics, and flexible optoelectronics, and by summarizing pertinent perspectives on current scientific challenges, application technology hurdles, and potential solutions for emerging scientific frontiers, this review aims to furnish fundamental guidance and conceptual frameworks for the design, advancement, and cutting‐edge application of novel mechanoluminescent materials. Zinc sulfide is a smart luminescent material with exceptionally outstanding mechanoluminescence properties. After over a century of research, it is now widely used in wearable devices, auxiliary lighting, stress sensing, anti‐counterfeiting, and other fields. This article comprehensively summarizes the properties, characteristics, mechanisms, preparation techniques, and application scenarios of zinc sulfide based on its features in mechanoluminescence. Constructively, it proposes future directions for optimization and methods for technological integration of zinc sulfide. Besides, the presentation of the challenges in mechanisms and applications also provide a unique perspective for subsequent research and assist researchers in quickly grasping the key focuses in this field.

Mechanoluminescent (ML) materials that directly convert mechanical energy into photon emission have emerged as promising candidates for various applications. Despite the recent advances in the development of both novel and conventional ML materials, the limited access to ML materials that simultaneously have the attributes of high brightness, low cost, self‐recovery, and stability, and the lack of appropriate designs for constructing ML devices represent significant challenges that remain to be addressed to boost the practical application of ML materials. Herein, ML hybrids derived from a natural source, waste eggshell, with the aforementioned attributes are demonstrated. The introduction of the eggshell not only enables the preparation of the hybrid in a simple and cost‐effective manner but also contributes to the homochromatism (red, green, or blue emission), high brightness, and robustness of the resultant ML hybrids. The significant properties of the ML hybrids, together with the proposed structural design, such as porosity or core–shell structure, could expedite a series of mechanic‐optical applications, including the self‐luminous shoes for the conversion of human motions into light and light generators that efficiently harvest water wave energy. The fascinating properties, versatile designs, and the efficient protocol of “turning waste into treasure” of the ML hybrids represent significant advances in ML materials, promising a leap to the practical applications of this flouring material family. Mechanoluminescence materials, converting the mechanical energy into photons directly, emerge to be of broad interest in the materials community. Here, the conversion of waste shells to high‐performance mechanoluminescence hybrids in a simple, eco‐friendly, and cost‐efficient manner is reported, enabling the versatile applications of mechanoluminescence materials in sensing, displaying, and energy harvesting.