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Based on the ultrafast and extremely strong interaction between laser pulses and materials, ultrafast laser irradiation can break the solid solubility constraints and enable hyperdoping of impurities. This process overcomes the bandgap constraints of crystalline silicon, resulting in heightened absorption across a broad spectral range spanning from ultraviolet to infrared wavelengths, therefore commonly referred to as black silicon (b‐Si). The b‐Si demonstrates significant changes in optoelectronic properties, making it highly promising for applications in silicon photonics. Specifically, b‐Si photodetectors exhibit distinct advantages in terms of high photoelectric gain at low voltage, ultrabroadband spectral responsivity, large dynamic range, and suitability for operation over a wide temperature range. These properties address the limitations of traditional silicon photodetectors, showcasing great potential for applications in optoelectronic integration, artificial intelligence, information technology, energy devices, and beyond. This review focuses on b‐Si achieved through ultrafast laser processing, with a special emphasis on its applications in photodetectors. The mechanism of ultrafast laser irradiation and the properties of hyperdoped silicon are discussed. Then, the research progresses and state‐of‐the‐art b‐Si photodetectors are introduced, as well as working mechanism and potential application expansion. Finally, the development prospects of b‐Si photodetectors based on ultrafast laser hyperdoping are predicted. [ABSTRACT FROM AUTHOR]

The development of efficient and selective organic synthetic approaches for complex molecules has garnered significant attention due to the need for precise control over molecular structures and functions. Rotaxanes, a type of mechanically interlocked molecules (MIMs), have shown promising applications in various fields including sensing, catalysis, and material science. However, the highly selective synthesis of oligo[n]rotaxanes (mostly n≥3) through controlling host‐guest complexation and supramolecular threading assembly process still remains an ongoing challenge. In particular, the utilization of two‐dimensional (2D) macrocycles with structural shape‐persistency for the synthesis of oligo[n]rotaxanes is rare. In this concept, research on cooperatively threaded host‐guest complexation with hydrogen‐bonded (H‐bonded) aramide macrocycles and selective synthetic protocols of oligo[n]rotaxanes has been summarized. The high efficiency and selectivity in synthesis are ascribed to the synergistic interplay of multiple non‐covalent bonding interactions such as hydrogen bonding and intermolecular π–π stacking of macrocycles within the unique supramolecular structure of threaded host‐guest complexes. This review focuses on the latest progress in the concepts, synthesis, and properties of H‐bonded aramide macrocycle‐based oligorotaxanes, and presents an in‐depth outlook on challenges in this emerging field. [ABSTRACT FROM AUTHOR]

Preclinical studies of nanoparticles for pulmonary therapeutics are often performed on 2D cell cultures or in vitro models that do not include a mucus barrier. However, the mucus layer lining the lungs is an essential barrier for drugs to permeate in order to exert a therapeutic effect. Herein, the role of surface coating of lanthanide‐doped upconverting nanoparticles (UCNPs) and their interaction with the mucus barrier are explored using a patient‐derived 3D cell culture model. The upconverted emissions from the UCNPs are used to track them throughout the 3D model and study their localization as a function of administration time and mucus thickness. Positively charged, ligand‐free, and negatively charged, supported lipid bilayer‐coated UCNPs are evaluated. A substantial difference in the residence time in mucus and mucociliary clearance of each type of UCNP is observed in a realistic and relevant model. As such, these results underscore the need for preclinical investigations in tissue models, especially with respect to the surface properties of the nanoparticles under study. [ABSTRACT FROM AUTHOR]