Visible-light-driven photochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar photochemistry. Resonant optical excitation of surface plasmons produces energetic hot electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying photophysical processes in hot electron generation and discusses various electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven hot electron photochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future opportunities for addressing the low reaction efficiencies in hot-electron-induced photochemistry.

Luminescence quenching at high dopant concentrations generally limits the dopant concentration to less than 1-5 mol% in lanthanide-doped materials, and this remains a major obstacle in designing materials with enhanced efficiency/brightness. In this work, we provide direct evidence that the major quenching process at high dopant concentrations is the energy migration to the surface (i.e., surface quenching) as opposed to the common misconception of cross-relaxation between dopant ions. We show that after an inert epitaxial shell growth, erbium (Er) concentrations as high as 100 mol% in NaY(Er)F/NaLuF core/shell nanocrystals enhance the emission intensity of both upconversion and downshifted luminescence across different excitation wavelengths (980, 800, and 658 nm), with negligible concentration quenching effects. Our results highlight the strong coupling of concentration and surface quenching effects in colloidal lanthanide-doped nanocrystals, and that inert epitaxial shell growth can overcome concentration quenching. These fundamental insights into the photophysical processes in heavily doped nanocrystals will give rise to enhanced properties not previously thought possible with compositions optimized in bulk.

Au-Plasmon-induced resonance energy transfer modulates the charge carrier energetics of ZnO nanosheets to trigger the stoichiometric conversion of methane into ethane and hydrogen.

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Complex symmetrical CuS nanostructures were synthesized in large scale by a simple wet chemical method at low temperature. As a semiconductor material with superstructure, CuS was well characterized and firstly introduced into PVDF to form nanocomposites. The substantial enhancement of wave absorption (À102 dB at 7.7 GHz) was observed by addition of CuS with a low filler loading (5 wt%). The mechanism for the enhanced wave absorbing properties was explained in detail.

To date, even though various kinds of nanomaterials have been evaluated over the years in order to develop effective cancer therapy, there is still significant challenges in the improvement of the capabilities of nano-carriers. Developing a new theranostic nanomedicine platform for imaging-guided, visualized cancer therapy is currently a promising way to enhance therapeutic efficiency and reduce side effects. Firstly, conventional imaging technologies are reviewed with their advantages and disadvantages, respectively. Then, advanced biomedical materials for multimodal imaging are illustrated in detail, including representative examples for various dual-modalities and triple-modalities. Besides conventional cancer treatment (chemotherapy, radiotherapy), current biomaterials are also summarized for novel cancer therapy based on hyperthermia, photothermal, photodynamic effects, and clinical imaging-guided surgery. In conclusion, biomedical materials for imaging-guided therapy are becoming one of the mainstream treatments for cancer in the future. It is hoped that this review might provide new impetus to understand nanotechnology and nanomaterials employed for imaging-guided cancer therapy.

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The preparation and operation of free swimming functionalized sperm micromotors (FSFSMs) as intelligent self‐guided biomotors with intrinsic chemotactic motile behavior are reported. The natural sperm biomotors are functionalized with a wide variety of synthetic nanoscale payloads, such as CdSe/ZnS quantum dots, doxorubicin hydrochloride drug coated iron‐oxide nanoparticles, and fluorescein isothiocyanate‐modified Pt nanoparticles via endocytosis. The FSFSMs display efficient self‐propulsion in various biological and environmental media with controllable swarming behavior upon exposure to a chemical attractant. As a new class of environmentally responsive smart biomotors, the control of the FSFSM speed is achieved by varying the solution osmolarity that leads to different flagellar lengths. High drug loading capacity and responsive release kinetics are obtained with such sperm biomotors. The transport of synthetic cargo can be guided by the intrinsic chemotaxis of the FSFSMs. The chemotactic characteristics, speed control mechanism, and responsive payload release of the FSFSMs are investigated. Such use of free swimming functionalized sperm cells as intelligent microscale biomotors offers considerable potential for diverse biomedical and environmental applications.