The design of white‐light phosphors is attractive in solid‐state lighting (SSL) and related fields. A new strategy in obtaining white light emission (WLE) from dual‐way photon energy conversion in a series of dye@MOF (LIFM‐WZ‐6) systems is presented. Besides the traditional UV‐excited one‐photon absorption (OPA) pathway, white‐light modulation can also be gained from the combination of NIR‐excited green and red emissions of MOF backbone and encapsulated dyes via two‐photon absorption (TPA) pathway. As a result, down‐conversion OPA white light was obtained for RhB+@LIFM‐WZ‐6 (0.1 wt %), BR‐2+@LIFM‐WZ‐6 (2 wt %), and APFG+@LIFM‐WZ‐6 (0.1 wt %) samples under 365 nm excitation. RhB+@LIFM‐WZ‐6 (0.05 wt %), BR‐2+@LIFM‐WZ‐6 (1 wt %) and APFG+@LIFM‐WZ‐6 (0.05 wt %) exhibit up‐conversion TPA white light under the excitation of 800, 790, and 730 nm, respectively. This new WLE generation strategy combines different photon energy conversion mechanisms together.

Long persistent luminescence (LPL) materials have been fascinating from ancient times till today, whereas the generation and modulation of LPL are still uncontrollable in most cases. In this paper, a smart responsive metal–organic framework (MOF, LIFM-WZ-1) was reported to combine resilient structural dynamics with reversible LPL modulation. At room temperature in air, the as-prepared LIFM-WZ-1 has a staggered packing structure with inhaled water molecules between cavities, exhibiting fluorescence (F)-dominated blue emission. Under vacuum or by mild heating, the water molecules can be exhaled by the lattice, resulting in a crystal structure (LIFM-WZ-1a) with a reduced a axis and intensified intermolecular interactions. This brings transition to green excimer (E) emission related with lowered energy states. Meanwhile, orange-colored room temperature phosphorescence (RTP) is also enhanced, giving an overall balanced F/E/RTP emission. More fascinatingly, red LPL is ignited in the dehydrated sample, which is dumb in the original LIFM-WZ-1 because of intensified singlet to triplet intersystem crossing, damped high-energy oscillation, and compatible heat dissipation. The above breathing-induced LPL turn-on process is reversible by facile cooling, exposing to wet air, or purging in water vapor. This constitutes a successful exemplification in modulating LPL by the dynamic MOF, which provides potential applications in sensing, anti-counterfeiting, display, and so on.

Long persistent luminescence (LPL) materials have au nique photophysical mechanism to store light radiation energy for subsequent release.H owever,i nc omparison to the common UV source,w hite-light (WL) and near-infrared (NIR) excited LPL is scarce.Herein we report ametal-organic supramolecular boxbased on aD-p-A-type ligand. Owing to the integrated one-photon absorption (OPA) and two-photon absorption (TPA) attributes of the ligand, the heavy-atom effect of the metal center,a sw ell as p-stackinga nd Jaggregation states in the supramolecular assembly,L PL can be triggered by all wavebands from the UV to the NIR region. This novel designed supramolecular kit to affordLPL by both OPAa nd TPAp athwaysp rovides potential applications in anti-counterfeiting,c amouflaging,d ecorating,a nd displaying, among others. Figure 4. a) TDDFT energy levels and possible ISC channels of Cd 2 L 2 . b-e) Demonstration models for the application of Cd 2 L 2 in b) camouflaging, c) anti-counterfeiting, d) decorating, and e) displaying.

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Two-dimensional (2D) metal–organic frameworks have exhibited a range of fascinating attributes, of interest to numerous fields. Here, a calcium-based metal-organic framework with a 2D layered structure has been designed. Dual emissions relating to intralayer excimers and interlayer trapped excitons are produced, showing excitation-dependent shifting tendency, characteristic of a low dimensional semiconductor nature. Furthermore, the layer stacking by weak van der Waals forces among dynamically coordinated DMF molecules enables exfoliation and morphology transformation, which can be achieved by ultrasound in different ratios of DMF/H2O solvents, or grinding under appropriate humidity conditions, leading to nano samples including ultrathin nanosheets with single or few coordination layers. The cutting down of layer numbers engenders suppression of interlayer exciton-related emission, resulting in modulation of the overall emitting color and optical memory states. This provides a rare prototypical model with switchable dual-channel emissions based on 2D-MOFs, in which the interlayer excitation channel can be reversibly tuned on/off by top-down exfoliation and morphology transformation.