The potential applications of covalent organic frameworks (COFs) can be further developed by encapsulating functional nanoparticles within the frameworks. However, the synthesis of monodispersed ...core@shell structured COF nanocomposites without agglomeration remains a significant challenge. Herein, we present a versatile dual-ligand assistant strategy for interfacial growth of COFs on the functional nanoparticles with abundant physicochemical properties. Regardless of the composition, geometry or surface properties of the core, the obtained core@shell structured nanocomposites with controllable shell-thickness are very uniform without agglomeration. The derived bowl-shape, yolk@shell, core@satellites@shell nanostructures can also be fabricated delicately. As a promising type of photosensitizer for photodynamic therapy (PDT), the porphyrin-based COFs were grown onto upconversion nanoparticles (UCNPs). With the assistance of the near-infrared (NIR) to visible optical property of UCNPs core and the intrinsic porosity of COF shell, the core@shell nanocomposites can be applied as a nanoplatform for NIR-activated PDT with deep tissue penetration and chemotherapeutic drug delivery.
The gradient-structure is ideal nanostructure for conversion-type anodes with drastic volume change. Here, we demonstrate an inorganic-organic competitive coating strategy for constructing ...gradient-structured ferroferric oxide-carbon nanospheres, in which the deposition of ferroferric oxide nanoparticles and polymerization of carbonaceous species are competitive and well controlled by the reaction thermodynamics. The synthesized gradient-structure with a uniform size of ~420 nm consists of the ferroferric oxide nanoparticles (4-8 nm) in carbon matrix, which are aggregated into the inner layer (~15 nm) with high-to-low component distribution from inside to out, and an amorphous carbon layer (~20 nm). As an anode material, the volume change of the gradient-structured ferroferric oxide-carbon nanospheres can be limited to ~22% with ~7% radial expansion, thus resulting in stable reversible specific capacities of ~750 mAh g
after ultra-long cycling of 10,000 cycles under ultra-fast rate of 10 A g
. This unique inorganic-organic competitive coating strategy bring inspiration for nanostructure design of functional materials in energy storage.
Smart wearable devices are extensively utilized across diverse domains due to their inherent advantages of flexibility, portability, and real-time monitoring. Among these, flexible sensors ...demonstrate exceptional pliability and malleability, making them a prominent focus in wearable electronics research. However, the implementation of flexible wearable sensors often entails intricate and time-consuming processes, leading to high costs, which hinder the advancement of the entire field. Here, we report a pressure and proximity sensor based on oxidized laser-induced graphene (oxidized LIG) as a dielectric layer sandwiched by patterned LIG electrodes, which is characterized by high speed and cost-effectiveness. It is found that in the low-frequency range of fewer than 0.1 kHz, the relative dielectric constant of the oxidized LIG layer reaches an order of magnitude of 10sup.4. The pressure mode of this bimodal capacitive sensor is capable of detecting pressures within the range of 1.34 Pa to 800 Pa, with a response time of several hundred milliseconds. The proximity mode involves the application of stimulation using an acrylic probe, which demonstrates a detection range from 0.05 mm to 37.8 mm. Additionally, it has a rapid response time of approximately 100 ms, ensuring consistent signal variations throughout both the approach and withdrawal phases. The sensor fabrication method proposed in this project effectively minimizes expenses and accelerates the preparation cycle through precise control of laser processing parameters to shape the electrode-dielectric layer-electrode within a single substrate material. Based on their exceptional combined performance, our pressure and proximity sensors exhibit significant potential in practical applications such as motion monitoring and distance detection.
The marine internet of things (MIoT), an increasingly important foundation for ocean development and protection, consists of a variety of marine distributed sensors under water. These sensors of the ...MIoT have always been highly dependent on batteries. To realize in situ power supply, a flexible seaweed-like triboelectric nanogenerator (S-TENG) capable of harvesting wave energy is proposed in this study. The flexible structure, designed with inspiration from the seaweed structure, processes extensive marine application scenarios. The bending and recovering of the S-TENG structure under wave excitations are converted to electricity. As the output performance increases with the number of parallel connected S-TENG units, an S-TENG system with multiple units could serve for floating buoys, coastal power stations, and even submerged devices. Through the demonstration experiments performed in this study, the flexible, low-cost S-TENG could become an effective approach to achieve a battery independent MIoT.
The pore structure imparts materials with a high specific surface area, enhances mass transfer efficiency, and alters the interfacial interactions between the material host and its surrounding ...environment, thereby bringing about significant changes in material performances. ...they successfully achieved an increased pore volume in MOF-303 without compromising its favorable water-uptake attributes, leading to an approximately 50% enhancement in water-harvesting ability. In a similar study, the research team led by Hailong Jiang placed UIO-66 MOF, with terephthalic acid as the ligand, in an acetic acid solution and subjected it to reflux heating. ...PCC-60 with hierarchical pores can achieve remarkably higher enantiomeric excess values in separating racemates.
Synthesis of hierarchically porous structures with uniform spatial gradient and structure reinforcement effect still remains a great challenge. Herein, we report the synthesis of zeolite@mesoporous ...silica core–shell nanospheres (ZeoA@MesoS) with a gradient porous structure through a micellar dynamic assembly strategy. In this case, we find that the size of composite micelles can be dynamically changed with the increase of swelling agents, which in situ act as the building blocks for the modular assembly of gradient mesostructures. The ZeoA@MesoS nanospheres are highly dispersed in solvents with uniform micropores in the inner core and a gradient tubular mesopore shell. As a nanoreactor, such hierarchically gradient porous structures enable the capillary-directed fast mass transfer from the solutions to inner active sites. As a result, the ZeoA@MesoS catalysts deliver a fabulous catalytic yield of ∼75% on the esterification of long-chain carboxylic palmitic acids and high stability even toward water interference, which can be well trapped by the ZeoA core, pushing forward the chemical equilibrium. Moreover, a very remarkable catalytic conversion on the C–H arylation reaction of large N-methylindole is achieved (∼98%) by a Pd-immobilized ZeoA@MesoS catalyst. The water tolerance feature gives a notable enhancement of 26% in catalytic yield compared to the Pd-dendritic mesoporous silica without the zeolite core.
Despite the importance of nanoparticle's multipods topology in multivalent-interactions enhanced nano-bio interactions, the precise manipulation of multipods surface topological structures is still a ...great challenge. Herein, the surface-kinetics mediated multi-site nucleation strategy is demonstrated for the fabrication of mesoporous multipods with precisely tunable surface topological structures. Tribulus-like tetra-pods Fe
O
@SiO
@RF&PMOs (RF = resorcinol-formaldehyde resin, PMO = periodic mesoporous organosilica) nanocomposites have successfully been fabricated with a centering core@shell Fe
O
@SiO
@RF nanoparticle, and four surrounding PMO nanocubes as pods. By manipulating the number of nucleation sites through mediating surface kinetics, a series of multipods mesoporous nanocomposites with precisely controllable surface topological structures are formed, including Janus with only one pod, nearly plane distributed dual-pods and tri-pods, three-dimensional tetrahedral structured tetra-pods, etc. The multipods topology endows the mesoporous nanocomposites enhanced bacteria adhesion ability. Particularly, the tribulus-like tetra-pods mesoporous nanoparticles show ~100% bacteria segregation and long-term inhibition over 90% after antibiotic loading.
Powering marine distributed buoys sustainably and cost-efficiently has always been challenging in the ocean environment. Triboelectric nanogenerators (TENG), thanks to their robustness, high ...efficiency and low cost in energy harvesting, has provided a novel solution to the long-term electrical power supply for a series of distributed systems (including buoys). In this study, a wave energy harvesting sandwich-like TENG (S-TENG) has been proposed. In the on-land forced motion experiments, the S-TENG yields much superior performances compared to previous tower-like TENG in terms of the power density. The studies also reveal that the electrical output increases linearly even with larger number of parallel connected S-TENG layers. Consequently, a buoy integrated with 7 parallel connected S-TENGs is studied through systematic wave basin experiments and the relevance of most hydrodynamic parameters (including wave height, frequency, direction as well as mooring system) have been revealed. The presented wave basin experiments are original in wave energy harvesting TENG research practice and prove to be very helpful in that they simulate the most close-to-real ocean environments in the lab. The studies are concluded with a 12 W high-brightness LED lit up on a navigation supporting buoy. This study has set a benchmark of achieving self-powered buoy with TENG, which can be extended to other marine distributed systems such as sensors and small robotics.
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•Sandwich structure boosting output power density of triboelectric nanogenerators.•Accessible power promotion through parallel nanogenerators in layers.•First time triboelectric nanogenerator tested in an advanced wave basin.•Self-powered navigation buoy achieved by triboelectric nanogenerator integration.
Nanomotors with active motion have recently attracted wide attention. Researchers have developed a series of nanomotors with different architectures and propulsion mechanisms and have also explored ...the application prospects of nanomotors in many fields. Yet, the present nanomotors with simple component and motion behaviors are still far from the ultimate goal of nanoscale robots with controlled sophisticated motions. With this goal in mind, researchers are no longer satisfied with just making nanoparticles move actively, but looking forward to achieving precise control of the motion behavior of nanomotors. With the advance in nanofabrication techniques, tuning the nanomotors’ motion by modulating the structure of nanoparticles has become a widely welcomed approach. This article reviews the self‐propelling mechanisms and the various synthesis methods of nanomotors. It is also systematically summarized how the composition, surface properties, size, and morphology of nanoparticles affect their motion behavior. Some outstanding works are highlighted, the shortcomings, challenges, and opportunities in the field are also discussed. It is believed that a thorough review of the architecture–motion relationships of nanomotors is beneficial for the development of the field toward nanoscale robots.
Recent development of nanomotors have focused on the precise control of nanomotor's motion. In this article, the self‐propelling mechanisms and the various synthesis methods of nanomotors are reviewed. Composition, surface properties, size and morphology of nanomotors are listed out as the four factors most significantly affecting the motion behavior, and some representative works are highlighted.
As an important branch of anisotropic nanohybrids (ANHs) with multiple surfaces and functions, the porous ANHs (p-ANHs) have attracted extensive attentions because of the unique characteristics of ...high surface area, tunable pore structures and controllable framework compositions, etc. However, due to the large surface-chemistry and lattice mismatches between the crystalline and amorphous porous nanomaterials, the site-specific anisotropic assembly of amorphous subunits on crystalline host is challenging. Here, we report a selective occupation strategy to achieve site-specific anisotropic growth of amorphous mesoporous subunits on crystalline metal-organic framework (MOF). The amorphous polydopamine (mPDA) building blocks can be controllably grown on the {100} (type 1) or {110} (type 2) facets of crystalline ZIF-8 to form the binary super-structured p-ANHs. Based on the secondary epitaxial growth of tertiary MOF building blocks on type 1 and 2 nanostructures, the ternary p-ANHs with controllable compositions and architectures are also rationally synthesized (type 3 and 4). These intricate and unprecedented superstructures provide a good platform for the construction of nanocomposites with multiple functionalities and understanding of the structure-property-function relationships.
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