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Long‐lasting radioluminescence scintillators have recently attracted substantial attention from both research and industrial communities, primarily due to their distinctive capabilities of converting and storing X‐ray energy. However, determination of energy‐conversion kinetics in these nanocrystals remains unexplored. Here we present a strategy to probe and unveil energy‐funneling kinetics in NaLuF4:Mn2+/Gd3+ nanocrystal sublattices through Gd3+‐driven microenvironment engineering and Mn2+‐mediated radioluminescence profiling. Our photophysical studies reveal effective control of energy‐funneling kinetics and demonstrate the tunability of electron trap depth ranging from 0.66 to 0.96 eV, with the corresponding trap density varying between 2.38×105 and 1.34×107 cm−3. This enables controlled release of captured electrons over durations spanning from seconds to 30 days. It allows tailorable emission wavelength within the range of 520–580 nm and fine‐tuning of thermally‐stimulated temperature between 313–403 K. We further utilize these scintillators to fabricate high‐density, large‐area scintillation screens that exhibit a 6‐fold improvement in X‐ray sensitivity, 22 lp/mm high‐resolution X‐ray imaging, and a 30‐day‐long optical memory. This enables high‐contrast imaging of injured mice through fast thermally‐stimulated radioluminescence readout. These findings offer new insights into the correlation of radioluminescence dynamics with energy‐funneling kinetics, thereby contributing to the advancement of high‐energy nanophotonic applications. [ABSTRACT FROM AUTHOR]

Long‐lasting radioluminescence scintillators have recently attracted substantial attention from both research and industrial communities, primarily due to their distinctive capabilities of converting and storing X‐ray energy. However, determination of energy‐conversion kinetics in these nanocrystals remains unexplored. Here we present a strategy to probe and unveil energy‐funneling kinetics in NaLuF4:Mn2+/Gd3+ nanocrystal sublattices through Gd3+‐driven microenvironment engineering and Mn2+‐mediated radioluminescence profiling. Our photophysical studies reveal effective control of energy‐funneling kinetics and demonstrate the tunability of electron trap depth ranging from 0.66 to 0.96 eV, with the corresponding trap density varying between 2.38×105 and 1.34×107 cm−3. This enables controlled release of captured electrons over durations spanning from seconds to 30 days. It allows tailorable emission wavelength within the range of 520–580 nm and fine‐tuning of thermally‐stimulated temperature between 313–403 K. We further utilize these scintillators to fabricate high‐density, large‐area scintillation screens that exhibit a 6‐fold improvement in X‐ray sensitivity, 22 lp/mm high‐resolution X‐ray imaging, and a 30‐day‐long optical memory. This enables high‐contrast imaging of injured mice through fast thermally‐stimulated radioluminescence readout. These findings offer new insights into the correlation of radioluminescence dynamics with energy‐funneling kinetics, thereby contributing to the advancement of high‐energy nanophotonic applications. [ABSTRACT FROM AUTHOR]

Radiotherapy (RT) utilizes the non‐invasive and high penetration X‐ray as the energy source to eliminate deep‐seated tumors. The efficacy of RT can be optimized by designing effective radiosensitizers and synergizing with other treatment methods. Glutathione (GSH)‐responsive radio‐sensitizing nanovesicles are designed with size‐transformability via self‐assembly of gold‐manganese oxide Janus nanoparticles (JNPs) encapsulating the near‐infrared fluorescence (NIR) dye (IR1061). In the presence of GSH, JNP vesicles (Ves) dissociate into smaller gold (Au) NPs and manganese ion (Mn2+) that not only penetrate into the deeper layers of the tumor but also deplete the GSH and trigger chemodynamic therapy (CDT) through a Fenton‐like reaction, which augments the efficacy of RT. In addition, the IR1061 released from the disintegrated nanostructures fluoresces in the NIR‐II window, and along with photoacoustic (PA) and magnetic resonance imaging (MRI) enables high precision tumor detection. The combination of JNP Ve and X‐ray irradiation achieves multimodal image‐guided ablation of subcutaneous as well as deep‐seated tumors in murine models. Therefore, this novel multimodal image‐guided RT/CDT therapeutic platform is a promising strategy in high‐precision tumor therapy. [ABSTRACT FROM AUTHOR]

Current X-ray imaging technologies involving flat-panel detectors have difficulty in imaging three-dimensional objects because fabrication of large-area, flexible, silicon-based photodetectors on highly curved surfaces remains a challenge1–3. Here we demonstrate ultralong-lived X-ray trapping for flat-panel-free, high-resolution, three-dimensional imaging using a series of solution-processable, lanthanide-doped nanoscintillators. Corroborated by quantum mechanical simulations of defect formation and electronic structures, our experimental characterizations reveal that slow hopping of trapped electrons due to radiation-triggered anionic migration in host lattices can induce more than 30 days of persistent radioluminescence. We further demonstrate X-ray luminescence extension imaging with resolution greater than 20 line pairs per millimetre and optical memory longer than 15 days. These findings provide insight into mechanisms underlying X-ray energy conversion through enduring electron trapping and offer a paradigm to motivate future research in wearable X-ray detectors for patient-centred radiography and mammography, imaging-guided therapeutics, high-energy physics and deep learning in radiology.Using lanthanide-doped nanomaterials and flexible substrates, an approach that enables flat-panel-free, high-resolution, three-dimensional imaging is demonstrated and termed X-ray luminescence extension imaging. [ABSTRACT FROM AUTHOR]

Thrombosis is a frequent predisposing factor in high‐mortality cardiovascular diseases, which underscores the urgent need to precisely diagnose thrombosis formation at a less severe stage. However, it is still challenging to realize in vivo early thrombosis imaging due to lack of high sensitivity/‐specificity molecular imaging strategy. To address such problems, thrombin‐activatable scintillating nanoprobes are developed for background‐free X‐ray‐excited luminescence (XEL) imaging of in vivo early thrombosis. The nanoprobes are constructed by designing bright XEL‐emitting lanthanide‐doped scintillator nanocrystals (NCs) with dye labeled‐peptide modification. Such nanoprobes show XEL‐off originally and enable robust turn‐on XEL upon thrombin‐specific cleavage of the peptide, resulting from the rational manipulation of energy transfer between dye and NCs. Specially, due to high tissue penetration depth and background‐free attributes in XEL imaging, this strategy achieves high‐efficiency XEL imaging of the early thrombosis on the basis of in situ elevated thrombin levels. Moreover, XEL and magnetic resonance imaging capabilities can be integrated to further improve imaging accuracy and monitor thrombosis progression. As such, the exploited strategy demonstrates a novel paradigm for realizing timely thrombosis imaging and provides a new readily tailorable platform for sensitive in vivo deep‐tissue imaging. [ABSTRACT FROM AUTHOR]