With the evolution of nanoscience and nanotechnology, studies have been focused on manipulating nanoparticle properties through the control of their size, composition, and morphology. As nanomaterial research has progressed, the foremost focus has gradually shifted from synthesis, morphology control, and characterization of properties to the investigation of function and the utility of integrating these materials and chemical sciences with the physical, biological, and medical fields, which therefore necessitates the development of novel materials that are capable of performing multiple tasks and functions. The construction of multifunctional nanomaterials that integrate two or more functions into a single geometry has been achieved through the surface-coating technique, which created a new class of substances designated as core–shell nanoparticles. Core–shell materials have growing and expanding applications due to the multifunctionality that is achieved through the formation of multiple shells as well as the manipulation of core/shell materials. Moreover, core removal from core–shell-based structures offers excellent opportunities to construct multifunctional hollow core architectures that possess huge storage capacities, low densities, and tunable optical properties. Furthermore, the fabrication of nanomaterials that have the combined properties of a core–shell structure with that of a hollow one has resulted in the creation of a new and important class of substances, known as the rattle core–shell nanoparticles, or nanorattles. The design strategies of these new multifunctional nanostructures (core–shell, hollow core, and nanorattle) are discussed in the first part of this review. In the second part, different synthesis and fabrication approaches for multifunctional core–shell, hollow core–shell and rattle core–shell architectures are highlighted. Finally, in the last part of the article, the versatile and diverse applications of these nanoarchitectures in catalysis, energy storage, sensing, and biomedicine are presented.

ZnO nanoparticles were generated by thermal decomposition of a binuclear zinc (II) curcumin complex as single source precursor. Thermal behavior of the precursor showed a considerable weight loss at about 374 °C by an exothermic reaction with a maximum weight loss rate of 14%/min. Complete decomposition of precursor was observed within 49 min with a heating rate of 10 °C/min. Synthesized nanoparticles have been characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and selected area electron diffraction microscopy. Results revealed monodispersed hexagonal zincite structure with an average size of 117 ± 4 nm

A general and facile method was used for preparation of water-soluble silica coated LaVO₄:Eu³⁺ core-shell nanoparticles. In the present study, we have discussed and compared the cytotoxicity characteristics of the synthesized LaVO₄:Eu³⁺ and silica coated LaVO₄:Eu³⁺ core-shell nanoparticles. X-ray diffraction (XRD), field-emission transmission electron microscopy (FE-TEM), energy dispersive X-ray analysis (EDX), Fourier-transform infrared spectroscopy (FTIR), UV/Vis absorption spectroscopy and photoluminescence spectroscopic techniques were employed to characterize the structure and morphology of the prepared products. To obtain high aqueous solubility, luminescent LaVO₄:Eu³⁺ nanoparticles were encapsulated with silica groups, giving the nanoparticles a negatively charged surface at physiological pH. The results of XRD confirm the formation of a well-crystallized LaVO₄:Eu³⁺ phase with a tetragonal zircon structure. Optical absorption spectra show that the optical properties of silica-coated LaVO₄:Eu³⁺ core-shell nanoparticles are related to their sizes and shapes. Further, in order to assess cytotoxicity, we investigated whether the LaVO₄:Eu³⁺ nanoparticles could alter biological samples once they enter human H522 and peripheral blood mono nuclear cells (PBMCs). An MTT assay was performed to measure the mitochondrial activity that reflects the number of viable cells. Silica coated LaVO₄:Eu³⁺ core-shell nanoparticles exhibited no significant effect on the viability of both types of cells up to 24 h after exposure. Strikingly, no dose effects were detected, even at highest concentrations.

Water deficit is a major challenge for sustainable global food security, especially, in arid and semi-arid regions. Nanotechnology is regarded as an effective tool for managing a wide range of environmental stresses by providing novel and practical solutions. A field experiment was conducted to assess the effects of zinc oxide nanoparticles ‘ZnO NPs’ (0, 50, 100 ppm) and silicon dioxide nanoparticles ‘SiO₂ NPs’ (0, 25, 50 ppm) as an exogenous application on the physiological indices, total yield and water use efficiency (WUE) of potato under water deficit conditions (50%, 75%, and 100% of crop evapotranspiration (ETc) water requirements). Water deficit significantly decreased most physiological indices and yield traits of potato, but increased proline content and WUE. In contrast, exogenous application of ZnO NPs and SiO₂ NPs to plants grown under different water deficit treatments resulted in an increase in leaf gas exchange, leaves relative water contents (LRWC), photosynthetic pigments, and leaf green index. Under different water deficit treatments, the highest total yield and harvest index traits were obtained from plants treated with ZnO-NPs-100 ppm followed by 50 ppm of ZnO and SiO₂ NPs, respectively. The highest WUE was recorded when the potato plants were irrigated with 50% ETc and exogenous treated with 100 ppm of ZnO NPs compared with fully irrigated plants. In conclusion, the exogenous application of ZnO NPs (100 ppm) can significantly mitigate the water deficit stress and improve the physiological, yield, and WUE of potato grown in arid regions under water deficit conditions.