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In recent years, metal-organic frameworks (MOFs) have been attracting ever more Interest owing to their fascinating structures and widespread applications. Among the optoelectronic materials, luminescent MOFs (LMOFs) have become one of the most attractive candidates in the fields of optics and photonics thanks to the unique characteristics of their frameworks. Luminescence from MOFs can originate from either the frameworks, mainly including organic linkers and metal ions, or the encapsulated guests, such as dyes, perovskites, and carbon dots. Here, we systematically review the recent progress in LMOFs, with an emphasis on the relationships between their structures and emission behaviour. On this basis, we comprehensively discuss the research progress and applications of multicolour emission from homogeneous and heterogeneous structures, host-guest hybrid lasers, and pure MOF lasers based on optically excited LMOFs in the field of micro/nanophotonics. We also highlight recent developments in other types of luminescence, such as electroluminescence and chemiluminescence, from LMOFs. Future perspectives and challenges for LMOFs are provided to give an outlook of this emerging field. We anticipate that this article will promote the development of MOF-based functional materials with desired performance towards robust optoelectronic applications. [ABSTRACT FROM AUTHOR]

Nanophotonics, which is mainly the study of the behavior of light-matter interaction at the wavelength scale, has developed into one of the most important branches in optics-related disciplines. Utilizing organic functional molecules as the building blocks of nanophotonic materials and devices has great potential due to the multiple advantages, including the molecular designability, good processability, tailorable properties, and so on. Small molecules exhibit a strong tendency to aggregate into lowdimensional structures through an assembly process. The morphologies of the formed products, which are tightly related to the stacking modes of the molecules, can be precisely controlled through the modulation of various intermolecular interactions. The optical properties of organic complex structures, assembled from one or more types of small molecules, show heavy dependence on the composition, distribution, as well as the topological structures, manifesting a strategy to acquire desired photonic properties via rational structural design and/or componential modulation. This tutorial review focuses on the relationship among various molecules, diverse structures and photonic properties, with emphasis on the controllable assembly processes to fabricate low-dimensional structures and assembly strategies to achieve requisite optofunctional properties. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) nanostructures, including nanorods, nanowires, nanotubes, etc., exhibit the quantum confinement effects in the other two dimensions. Nanomaterials with 1D coherence are more suitable for the construction of active nanodevices and interconnects rather than zero-dimensional (0D) amorphous nanoparticles. Inorganic 1D nanomaterials have been widely investigated and widely used as building blocks in many kinds of optoelectronic integrations, and it is very reasonable to assume that their organic counterparts can also play an important role in this field. During the past ten years, organic 1D nanomaterials constructed from small functional molecules have obtained more and more attention due to their unique optical and electronic properties as well as their potential applications in nanoscale devices. Their high structural tunability, reaction activity and processability provide great opportunities to miniaturized optoelectronic chips based on organic 1D nanostructures, since they are usually assembled from molecular units with weak intermolecular interactions, such as hydrogen bonds, π–π stacking and van der Waals force. These weak interactions allow for more facile and mild conditions in the fabrication of high quality organic 1D nanostructures rather than those in the construction of their inorganic counterparts. More importantly, very recent studies reveal that the diversity of energy/electron transfer processes in organic semiconductors brings new hopes to break the performance limitations of traditional photonic and electronic devices, thus allowing higher luminescence intensity, more efficient photon confinement, stronger exciton–photon coupling, and so on. Indeed, organic 1D nanomaterials have already emerged to play increasingly an important role in many optoelectronic applications, such as nanolasers, optical waveguides, light-emitting devices, solar cells and sensors. In the past two decades, people have not only witnessed but also taken for granted the rapid development of nanomaterial science, and here we would like to promote awareness of the significance of organic 1D nanomaterials in the field of nanotechnology and optoelectronic nanodevices. This report presents a comprehensive review about recent research in the preparation and applications of 1D nanomaterials from functional low-molecular-weight organic compounds, whose optical and electronic properties are fundamentally different from those of their inorganic counterparts. Here we try to summarize the important breakthroughs from the fabrication of organic nanorods, nanowires and nanotubes, to the application of these nanostructures in integrated photonic elements and optoelectronic nanodevices. We begin with a general summary of the construction strategies (liquid-phase assembly, vapor deposition and template methods) for achieving 1D nanostructures from small organic functional molecules, then provide an overview of the unique optoelectronic properties induced by molecular aggregation in the nanostructures. Special emphasis is put on the luminescent properties of low dimensional sizes that are different from those of the corresponding bulk materials. This offers the materials better photon confinement ability or charge carrier transport property, and hence better optoelectronic performances such as optical waveguiding, multicolor emission, low-threshold nanolasers, light-emitting devices, photon-detecting devices, etc., which are presented one by one in the following section. In the last part of this report, we conclude with our personal viewpoints of the future development of organic 1D nanomaterials and also their great potentials in highly integrated photonic and electronic devices and chips. [ABSTRACT FROM AUTHOR]

Single-crystal ZnS1−xSexnanoribbons with various compositions were synthesized through an Au-catalyzed vapor transport method. Under two-photon pumping with an 800 nm femtosecond pulsed laser, the spontaneous emission peak of the ternary nanoribbons undergoes a gradual red-shift from 422 to 464 nm with the increase of Se content. When the pump energy densities are increased above the thresholds, the nanoribbons exhibit a tunable upconverted laser emission accompanied by a dramatic decrease in spectral linewidth as a set of sharp peaks on the corresponding wavelengths of each sample, featuring the occurrence of stimulated emission. Two components appear in the fluorescence lifetimes, which indicate that the ZnS1−xSexnanoribbons have two different recombination centers. Both lifetime components decrease with the increase of pump energy, further confirming the occurrence of stimulated emission. The two-photon pumped lasing behavior was also observed from single nanoribbons, in which the photoluminescence (PL) spectra are composed of multimode of lasing. The distinct modes show gain competition and pronounced shifts as a function of excitation density. [ABSTRACT FROM AUTHOR]

Fluorescence resonance energy transfer in conjugated polymer composite materials was exploited for the detection of γ ray dosage with high sensitivity and response linearity. [ABSTRACT FROM AUTHOR]

Two classes of bulk high-Zpolymer composites were prepared, which exhibit scintillation properties for γ-radiation detection. [ABSTRACT FROM AUTHOR]