Search Results (249)

Asymmetric nanomotors are a class of self-propelled nanoparticles that exhibit asymmetries in shape, composition, or surface properties. Their unique asymmetry, combined with nanoscale dimensions, endows them with significant potential in environmental and biomedical fields. For instance, glutathione (GSH) induced chemotactic nanomotors can respond to the overexpressed glutathione gradient in the tumor microenvironment to achieve autonomous chemotactic movement, thereby enhancing deep tumor penetration and drug delivery for efficient induction of ferroptosis in cancer cells. Moreover, self-assembled spearhead-like silica nanomotors reduce fluidic resistance owing to their streamlined architecture, enabling ultra-efficient catalytic degradation of lipid substrates via high loading of lipase. This review focuses on three core areas of asymmetric nanomotors: scalable fabrication (covering synthetic methods such as template-assisted synthesis, physical vapor deposition, and Pickering emulsion self-assembly), propulsion mechanisms (chemical/photo/biocatalytic, ultrasound propelled, and multimodal driving), and functional applications (environmental remediation, targeted biomedicine, and microelectronic repair). Representative nanomotors were reviewed through the framework of structure–activity relationship. By systematically analyzing the intrinsic correlations between structural asymmetry, energy conversion efficiency, and ultimate functional efficacy, this framework provides critical guidance for understanding and designing high-performance asymmetric nanomotors. Despite notable progress, the prevailing challenges primarily reside in the biocompatibility limitations of metallic catalysts, insufficient navigation stability within dynamic physiological environments, and the inherent trade-off between propulsion efficiency and biocompatibility. Future efforts will address these issues through interdisciplinary synthesis strategies. Full article

This study introduces novel experimental systems that facilitate the nucleation, growth, aggregation, and agglomeration of ionic salt solutions, leading to structurally and functionally distinctive crystal formations. Through evaporative crystallization in hanging drops—including layered binary solutions—a range of macroscopic agglomerates were produced, such as hollow spheroidal NaCl/NiSO₄ structures, octahedral NaCl films, pentagonally arranged CdSO₄ spherulites, and NH₄Cl dendritic shells. Additionally, NaCl spheroids were used as templates to fabricate carbon-based morphologies and colloidal photonic crystals with convex or concave geometries, which were subsequently analyzed optically. The study reveals that crystallization and self-assembly, whether independently or synergistically applied, can yield complex architectures with potential applications in advanced device manufacturing beyond conventional processing methods. Full article

Three-dimensional (3D) surface-enhanced Raman scattering (SERS) substrates have demonstrated remarkable abilities of ultrasensitive and reproducible molecular detection. The combination of both electromagnetic and chemical enhancement processes, light trapping, and multiple scattering effects of 3D structures are what enhance their performance. The principles of underlying enhancements are summarized systematically, and the main types of 3D substrates—vertically aligned nanowires, dendritic and fractal nanostructures, porous frameworks and aerogels, core–shell and hollow nanospheres, and hierarchical hybrid structures—are categorized in this review. Advances in fabrication techniques, such as template-assisted growth, electrochemical and galvanic deposition, dealloying and freeze-drying, self-assembly, and hybrid integration, are critically evaluated in terms of structural tunability and scalability. Novel developments in the field of biosensing are also highlighted, including non-enzymatic glucose sensing, tumor biomarker sensing, and drug delivery. The remaining limitations, such as low reproducibility, mechanical stability, and substrate standardization, are also noted, and future directions, such as stimuli-responsive designs, multifunctional hybrid platforms, and data-driven optimization strategies of SERS technologies, are also included. Full article

Bionic synthesis technology has made significant breakthroughs in porous functional materials by replicating and optimizing biological structures. For instance, biomimetic titanium dioxide-coated carbon multilayer materials, prepared via biological templating, exhibit a hierarchical structure, abundant nanopores, and synergistic effects. Bionic mineralization further enhances microcapsules by forming a secondary inorganic wall, granting them superior impermeability, high elastic modulus, and hardness. Through techniques like molecular self-assembly, electrospinning, and pressure-driven fusion, researchers have successfully fabricated centimeter-scale artificial lamellar bones without synthetic polymers. In environmental applications, electrospun membranes inspired by lotus leaves and bird bones achieve 99.94% separation efficiency for n-hexane–water mixtures, retaining nearly 99% efficiency after 20 cycles. For energy applications, an all-ceramic silica nanofiber aerogel with a bionic blind bristle structure demonstrates ultralow thermal conductivity (0.0232–0.0643 W·m⁻¹·K⁻¹) across a broad temperature range (−50 to 800 °C). This review highlights the preparation methods and recent advances in biomimetic porous materials for practical applications. Full article

The interest in macromolecular alkoxysilyl-functionalized hybrids (self-assembling or nanostructured), which could be used as precursors in biomimetic silica precipitation and for the synthesis of hollow spherical silica particles, is growing. Nevertheless, reports on all-organosilicon systems for bioinspired silica precipitation are scarce. Therefore, a new kind of polyalkoxysilane macromonomer–linear polysilsesquioxane (LPSQ) of ladder-like backbone, functionalized in side chains with trimethoxysilyl groups (LPSQ-R-Si(OMe)₃), was designed following this approach. It was obtained by photoinitiated thiol-ene addition of 3-mercaptopropyltrimethoxysilane to the vinyl-functionalized polysilsesquioxane precursor, carried out in situ in tetraethoxysilane (TEOS). The mixture of LPSQ-R-Si(OMe)₃ and TEOS (co-monomers) was used in a sol–gel process conducted under acidic conditions (0.5 M HCl/NaCl) in the presence of Pluronic^® F-127 triblock copolymer as a template. LPSQ-R-Si(OMe)₃ played a key role for the formation of microparticles of a spherical shape that were formed under the applied conditions, while their size (as low as 3–4 µm) was controlled by the stirring rate. The hybrid materials were hydrophobic and showed good thermal and oxidative stability. Introduction of zinc acetate (Zn(OAc)₂) as an additive in the sol–gel process influenced the pH of the reaction medium, which resulted in structural reinforcement of the hybrid microparticles owing to more effective condensation of silanol groups and a relative increase of the content of SiO₂. The proposed method shows directions in designing the properties of hybrid materials and can be translated to other silicon–organic polymers and oligomers that could be used to produce hollow silica particles. The established role of various factors (macromonomer structure, pH, and stirring rate) allows for the modulation of particle morphology. Full article

Janus nanoparticles (JNPs) extend the concept of amphiphilicity beyond classical molecular surfactants into the nanoscale. Amphiphilic behavior is defined by the presence of hydrophobic and hydrophilic moieties within a single molecular structure. Traditionally, such molecular structures are known as surfactants or amphiphiles and are capable of reducing interfacial tension, adsorbing spontaneously at interfaces, stabilizing emulsions and foams, and forming micelles, bilayers, or vesicles. Recent experimental, theoretical, and computational studies demonstrate that these behaviors are scalable to nanostructured colloids such as JNPs. Amphiphilic JNPs, defined by anisotropic surface chemistry on distinct hemispheres, display interfacial activity driven by directional wetting, variable interfacial immersion depth, and strong interfacial anchoring. They can stabilize liquid/liquid and liquid/gas interfaces, and enable templated or spontaneous self-assembly into supra-structures, such as monolayer sheets, vesicles, capsules, etc., both in bulk and at interfaces. Their behavior mimics the “soft” molecular amphiphiles but also includes additional particularities given by their “hard” structure, as well as contributions from capillary, van der Waals, hydrophobic, and shape-dependent forces. This review focuses on compiling the evidence supporting amphiphilicity as a scalable property, discussing how JNPs function as colloidal amphiphiles and how geometry, polarity contrast, interfacial interactions, and environmental parameters influence their behavior. By comparing surfactant behavior and JNP assembly, this work aims to clarify the transferable principles, the knowledge gap, as well as the emergent properties associated with amphiphilic Janus colloids. Full article

Diuron (DU) is a widely used phenylurea herbicide designed to inhibit weed growth, but its high toxicity and prolonged half-life contribute significantly to environmental contamination. The majority of electrochemical (EC) sensors typically rely on a single response signal for the detection of DU, rendering them highly susceptible to interference from variable background noise in complex environments, thereby reducing the selectivity and robustness. By integrating molecularly imprinted polymer (MIP) with a ratiometric strategy, the aforementioned issues could be solved. In this study, a novel signal on-off ratiometric MIP-EC sensor was developed based on the MXene/PEI-MWCNTs nanocomposite for the detection of DU. Positively charged PEI-MWCNTs was used as an interlayer spacer and embedded into negatively charged MXene by a simple electrostatic self-assembly method. This effectively prevented the agglomeration of MXene and enhanced its electrocatalytic performance. The MIP was synthesized via electropolymerization with DU serving as the template molecule and the selectivity was enhanced by leveraging the gate effect of MIP. Subsequently, a ratiometric MIP-EC sensor was designed by introducing [Fe(CN)₆]^3−/4− into the electrolyte solution as an internal reference. Additionally, the current ratio signal (I_DU/I_[Fe(CN)6]^3−/4−) and DU concentration exhibited a good linear relationship within the range of 0.1 to 100 µM, with a limit of detection (LOD) of 30 nM (S/N = 3). In comparison with conventional single-signal MIP-EC sensing, the developed ratiometric MIP-EC sensing demonstrates superior reproducibility and accuracy. At the same time, the proposed sensor was successfully applied to the quantitative analysis of DU residues in soil samples, yielding highly satisfactory results. Full article

This study develops a one-pot anodic templating electrodeposition strategy using dual-cation-crosslinking and interpenetrating networks, coupled with pulsed electrical signals, to fabricate a vessel-mimetic multilayered tubular hydrogel. Typically, the anodic electrodeposition is performed in a mixture of sodium alginate (SA) and carboxymethyl chitosan (CMC), with the ethylenediaminetetraacetic acid calcium disodium salt hydrate (EDTA·Na₂Ca) incorporated to provide a secondary ionic crosslinker (i.e., Ca²⁺) and modulate the cascade reaction diffusion process. The copper wire electrodes serve as templates for electrochemical oxidation and enable a copper ion (i.e., Cu²⁺)-induced tubular hydrogel coating formation, while pulsed electric fields regulate layer-by-layer deposition. The dual-cation-crosslinked interpenetrating hydrogels (CMC/SA-Cu/Ca) exhibit rapid growth rates and tailored mechanical strength, along with excellent antibacterial performance. By integrating the unique pulsed electro-fabrication with biomimetic self-assembly, this study addresses challenges in vessel-mimicking structural complexity and mechanical compatibility. The approach enables scalable production of customizable multilayered hydrogels for artificial vessel grafts, smart wound dressings, and bioengineered organ interfaces, demonstrating broad biomedical potential. Full article

Hierarchical porous N-doped carbon spheres featuring a combination of micropores, mesopores and macropores as well as tuneable properties were synthesised using dopamine as a carbon precursor and triblock copolymers (F127, P123 and F127/P123 composites) as templates via direct polymerisation-induced self-assembly. The structures and textures of these materials were characterised using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N₂ adsorption–desorption isotherm analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The sample synthesised at an F127:P123 molar ratio of 1:3 (NCS-FP3) exhibited the highest surface area (463 m²/g) and pore volume (0.27 cm³/g). The hydrophobic/hydrophilic molar ratios of the templates were adjusted to control the morphology of the corresponding micelles and hence the porous structures and morphologies of the carbon spheres, which exhibited high CO₂ capture capacities (2.90–3.46 mmol/g at 273 K and 760 mmHg) because of their developed microporous structures and N doping. Additionally, NCS-FP3 exhibited an outstanding electrochemical performance, achieving a high specific capacitance (328.3 F/g at a current density of 0.5 A/g) and outstanding cycling stability (99.2% capacitance retention after 10,000 cycles). These high CO₂ capture and electrochemical performances were ascribed to the beneficial effects of pore structures and surface chemistry features. Full article

Precise control over molecular dispersity and supramolecular assembly is essential for designing nanostructures with targeted properties and functionalities. In this study, we explore the impact of molecular dispersity in BTA-oligo(AA)₃ oligomers on the formation and structural organization of Au nanomaterials in an aqueous system. Discrete and polydisperse BTA-oligo(AA)₃ samples are systematically synthesized and characterized to evaluate their role as templates for nanostructure formation. UV-vis spectroscopy and TEM analyses reveal distinct differences in the resulting nanostructures. Specifically, discrete oligomers facilitate the formation of well-defined, interconnected Au nanonetworks with high structural uniformity, even at elevated concentrations. In contrast, polydisperse oligomers facilitated the formation of isolated Au nanoparticles with limited control over morphology and connectivity. These differences are attributed to the greater molecular uniformity and enhanced self-assembly capabilities of the discrete oligomers, which serve as effective templates for directing Au precursor organization and reduction into ordered nanostructures. This study provides mechanistic insight into how molecular dispersity affects the templating and assembly of gold nanomaterials. The findings offer a promising strategy for developing tailored nanostructures with interconnected morphologies and controlled optical and structural properties, paving the way for advanced applications. Full article

Directed self-assembly (DSA) lithography, a cutting-edge technology based on the self-assembly of block copolymers (BCPs), has received significant attention in recent years. Combining DSA with established lithography technologies, such as extreme ultraviolet (EUV), deep ultraviolet (DUV), electron beam lithography, and nanoimprint lithography, significantly enhances the resolution of target patterns and device density. Currently, there are two commonly used methods in DSA: graphoepitaxy, employing lithographically defined topographic templates to guide BCP assembly, and chemoepitaxy, utilizing chemically patterned surfaces with precisely controlled interfacial energies to direct nanoscale phase segregation. Through novel DSA lithography technology, nanoscale patterns with smaller feature sizes and higher densities can be obtained, realizing the miniaturization of hole and line patterns and pitch multiplication and improving the roughness and local critical dimension uniformity (LCDU). It is gradually becoming one of the most promising and advanced lithography techniques. DSA lithography technology has been applied in logic, memory, and optoelectronic device fabrications. Full article

Two-dimensional nanomaterials (2DNMs) exhibit significant potential for the development of functional and specifically targeted biosensors, owing to their unique planar nanosheet structures and distinct physical and chemical properties. Biomodification and biomimetic synthesis offer green and mild approaches for the fabrication of multifunctional nanohybrids with enhanced catalytic, fluorescent, electronic, and optical properties, thereby expanding their utility in constructing high-performance biosensors. In this review, we present recent advances in the synthesis of 2DNM-based nanohybrids via both biomodification and biomimetic strategies for biosensor applications. We discuss covalent and non-covalent biomodification methods involving various biomolecules, including peptides, proteins, DNA/RNA, enzymes, biopolymers, and bioactive polysaccharides. The engineering of biomolecule–nanomaterial interfaces for the creation of biomodified 2DNM-based nanohybrids is also explored. Furthermore, we summarize the biomimetic synthesis of 2DNM-based bio–nanohybrids through pathways such as bio-templating, biomolecule-directed self-assembly, biomineralization, and biomimetic functional integration. The potential applications of these nanohybrids in diverse biosensing platforms—including colorimetric, surface plasmon resonance, electrochemical, fluorescence, photoelectrochemical, and integrated multimodal biosensors—are introduced and discussed. Finally, we analyze the opportunities and challenges associated with this rapidly developing field. We believe this comprehensive review will provide valuable insights into the biofunctionalization of 2DNMs and guide the rational design of advanced biosensors for diagnostic applications. Full article

Traditional nanoparticle aerogels suffer from inherent brittleness and thermal instability at elevated temperatures. In recent years, ceramic nanofiber aerogels, utilizing flexible nanofibers as structural units, have emerged as mechanically resilient alternatives with ultrahigh porosity (>90%). However, their thermal insulation capabilities are compromised by micron-scale pores (10–100 μm) and overdependence on ultralow density, which exacerbates mechanical fragility. This study pioneers a gas-phase self-assembly strategy to fabricate Si₃N₄ nanoparticle reinforced Si₃N₄ nanofiber aerogels (SNP-R-SNFA) with gradient pore architectures. By leveraging methyltrimethoxysilane/vinyltriethoxysilane composite aerogel (MVa) as a reactive template, we achieved spontaneous growth of Si₃N₄ nanofiber films (SNP-R-SNF) featuring nanoparticle-fiber interpenetration and porosity gradients. The microstructure formation mechanism of SNP-R-SNF was analyzed using field-emission scanning electron microscopy. Layer assembly and hot-pressing composite technology were employed to prepare the SNP-R-SNFA, which showed low density (0.033 g/cm³), exceptional compression resilience, insensitive frequency dependence of dielectric properties (ε′ = 2.31–2.39, tan δ < 0.08 across 8–18 GHz). Infrared imaging displayed backside 893 °C cooler than front, demonstrating superior insulation performance. This study not only provides material solutions for integrated electromagnetic wave-transparent/thermal insulation applications but more importantly establishes an innovative paradigm for enhancing the mechanical robustness of nanofiber-based aerogels. Full article

Designing bifunctional catalysts for efficient hydroisomerization of phenanthrene to alkyl-adamantane is a great challenge for producing high-density fuels. Herein, a bifunctional Pt catalyst was fabricated by developing hierarchical H-MSY-T zeolites with an NOA-co strategy. The influence of different mesopore template agents on the hierarchical structure of H-MSY-T zeolite was investigated. Effective regulation of pore structure and acid distribution of zeolites was achieved by adjusting the templating agents. The block copolymer P123 promoted the formation of mesoporous structures via self-assembly with a large mesopore centered at 8 nm. Large mesoporous structure and suitable distribution of Bronsted acid boosted the hydroisomerization of phenanthrene. The highest alkyl-adamantane yield of 45.9 wt% was achieved on the Pt/MSY-P1 catalyst and a reaction network of hydroisomerization was proposed. This work provides guidance to design highly selective bifunctional catalysts for the one-step hydroconversion of tricyclic aromatic hydrocarbons into high-density fuels. Full article

Significant research has focused on cost–effective, highly active, and exceptionally stable non–noble metal electrocatalysts (NNMEs) to boost the performance of the oxygen reduction reaction (ORR). Of note, the development of design and synthesis of Fe–N–C electrocatalysts is essential but remains challenging. Herein, the Fe and N co–doped porous carbon material with a yolk–shell (YS) structure, termed SA–H₂TPyP@PDA–Fe (900), was fabricated by self–assembly of metal–free porphyrin as a yolk and polymerization of dopamine as a shell with an addition of iron salts, followed by the high–temperature pyrolysis and acid–leaching. As a result, active sites, like FeN₄ and N–doped C, within rich porous YS carbon structures, play an important role for ORR in an alkaline media. The SA–H₂TPyP@PDA–Fe (900) electrocatalyst shows positive ORR performances than those of SA–H₂TPyP (900) and SA–H₂TPyP@PDA (900), indicating the dominating function of the YS carbon structure decorated with Fe–based species. This efficient route of template–free–induced preparation of the YS structure discovers the design and synthesis of NNMEs for ORR. Full article