The development of materials with outstanding performance for sensitive and selective detection of multiple analytes is essential for the development of human health and society. Luminescent metal–organic frameworks (LMOFs) have controllable surface and pore sizes and excellent optical properties. Therefore, a variety of LMOF-based sensors with diverse detection functions can be easily designed and applied. Furthermore, the introduction of energy transfer (ET) into LMOFs (ET-LMOFs) could provide a richer design concept and a much more sensitive and accurate sensing performance. In this review, we focus on the recent five years of advances in ET-LMOF-based sensing materials, with an emphasis on photochemical and photophysical mechanisms. We discuss in detail possible energy transfer processes within a MOF structure or between MOFs and guest materials. Finally, the possible sensing applications of the ET-LMOF-based sensors are highlighted.

Scintillators are critical for high-energy radiation detection across a wide array of potential applications, from medical radiography and safety inspections all the way to space exploration. However, constrained by their current shortcomings, including high-temperature and complex fabrication as well as inherent brittleness and fragility among thick films and bulk crystals, traditional scintillators are finding it difficult to meet the rising demand for cost-effective, ecofriendly, and flexible X-ray detection. Here, we describe the development of high-performance and flexible X-ray scintillators based on films of Cu-doped Cs2AgI3 that exhibit ultrahigh X-ray sensitivity. The materials exhibit a high scintillation light yield of up to 82 900 photons/MeV and a low detection limit of 77.8 nGy/s, which is approximately 70 times lower than the dosage for a standard medical examination. Moreover, richly detailed X-ray images of biological tissue and electronic components with a high spatial resolution of 16.2 lp/mm were obtained using flexible, large-area, solution-processed scintillation screens.

Copper-based halide scintillators have attracted considerable interest because of their high light yields, low detection limits, low toxicity, and moderate fabrication conditions. Here, we synthesized two Cu(I) iodide inks, comprising zero-dimensional Cu 4 I 6 (L 1 ) 2 nanoparticles (L 1 = 1-propyl-1,4-diazabicyclo[2.2.2]octan-1-ium) and one-dimensional Cu 4 I 6 (L 2 ) 2 nanorods (L 2 = 4-dimethylamino-1-ethylpyridinium) for X-ray imaging application. The Cu 4 I 6 (L 1 ) 2 nanoparticles and Cu 4 I 6 (L 2 ) 2 nanorods exhibited broadband green and yellow emission with an ultrahigh photoluminescence quantum yield of 95.3% and 92.2%, respectively. Consequently, the two Cu(I) iodide ink-based X-ray screens exhibited low detection limits of 96.4 and 102.1 nGy s −1 , respectively, which are approximately 55 times lower than the dose required for standard medical diagnosis (5.5 μGy s −1 ). Importantly, both the scintillation screens exhibited extraordinary X-ray imaging resolutions exceeding 30 lp mm −1 , more than double those of the conventional CsI:Tl and Ga 2 O 2 S:Tb scintillators. This study provides a new avenue for exploring high-resolution X-ray imaging screens on the basis of Cu-based halide ink for medical radiography and nondestructive detection.

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We report a series of organic fluorophores that undergo selective self-sensitized photooxidation upon light irradiation in air.