copy and easy to authenticate) is the primary approach for resisting the increasing sophistication of counterfeiting. [1] Due to their visual identifiability, colorful light emissions of luminophors are considered to be ideal security elements. The luminescent patterns of banknotes under ultraviolet (UV) excitation are a well-known sample of this approach. In addition to the spatial spectral fingerprints displayed in emission colors, the excitation mode and emission lifetime of luminescence can be used as authentication information, providing higher coding levels. For example, photoluminescence (PL), upconversion luminescence (UCL), and long-lasting luminescence (LLL) are three quintessential modes for anticounterfeiting and information security. [2] The PL mode produces photons at longer wavelengths than the excitation wavelength, for example, downshifting UV excitation to visible emission. [3] The UCL mode converts longwavelength photons to short-wavelength ones, for example, in the upconversion of near-infrared (NIR) excitation to visible emission. [4] It is important to note that PL and UCL phenomena will disappear immediately once light excitation is stopped, showing a feature of pulse duration (so-called fluorescence). In contrast, LLL shows delayed initiation after the cessation of Optical characteristics of luminescent materials, including emission color (wavelength), lifetime, and excitation mode, play crucial roles in data communication and information security. Conventional luminescent materials generally display unicolor, unitemporal, and unimodal (occasionally bimodal) emission, resulting in low-level readout and decoding. The development of multicolor, multitemporal, and multimodal luminescence in a single material has long been considered to be a significant challenge. In this study, for the first time, the superior integration of colorful (red-orange-yellowgreen), bitemporal (fluorescent and delayed), and four-modal (thermo-/ mechano-motivated and upconverted/downshifted) emissions in a particular piezoelectric particle via optical multiplexing of dual-lanthanide dopants is demonstrated. The as-prepared versatile NaNbO 3 :Pr 3+ ,Er 3+ luminescent microparticles shown are particularly suitable for embedding into polymer films to achieve waterproof, flexible/wearable and highly stretchable features, and synchronously to provide multidimensional codes that can be visually read-out using simple and commonly available tools (including the LED of a smartphone, pen writing, cooling-heating stimuli, and ultraviolet/ near-infrared lamps). These findings offer unique insight for designing highly integrated stimuli-responsive luminophors and smart devices toward a wide variety of applications, particularly advanced anticounterfeiting technology.

.[1] The earliest formed crust on a single plate planet such as Mars should be preserved, deeply buried under subsequent surface materials. Mars' extensive cratering history would have fractured and disrupted the upper layers of this ancient crust. Large impacts occurring late in Martian geologic history would have excavated and exposed this deeply buried material. We report the compositional analysis of unaltered mafic Martian crater central peaks with high-resolution spectral data that was used to characterize the presence, distribution and composition of mafic mineralogy. Reflectance spectra of mafic outcrops are modeled with the Modified Gaussian Model (MGM) to determine cation composition of olivine and pyroxene mineral deposits. Observations show that central peaks with unaltered mafic units are only observed in four general regions of Mars. Each mafic unit exhibits spectrally unmixed outcrops of olivine or pyroxene, indicating dunite and pyroxenite dominated compositions instead of basaltic composition common throughout much of the planet. Compositional analysis shows a wide range of olivine Fo# ranging from Fo 60 to Fo 5 . This variation is best explained by a high degree of fractionation in a slowly cooling, differentiating magma body. Pyroxene analysis shows that all the sites in the Southern Highlands are consistent with moderately Fe-rich, low-Ca pyroxene. Mineral segregation in the ancient crust could be caused by cumulate crystallization and settling in a large, potentially global, lava lake or near surface plutons driven by a hypothesized early Martian mantle overturn.

Piezoluminescence has achieved enormous advancement in the field of stress sensors, and mechano-driven lightings and displays; however the existing piezoluminescent materials universally need the external dopants of lanthanide or transition metal ions to create efficient luminescence. Herein, we report a bright piezoluminescence in undoped piezoelectric semiconductor CaZnOS, which is multi-mechano-sensitive to ultrasonic vibration, friction, impact and compression. Our experimental and density functional theory computational investigations indicate that the intrinsic oxygen vacancies of VO2+, VO+ and VO0 act as luminescent centers and trap states in multi-colored components of luminescence. In addition to saving resources and protecting environment, our research is expected to open a door for design and development of self-piezoluminescent materials, thereby largely expanding our understanding of piezoluminescent mechanism and promoting further utilization of piezoluminescence.

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