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Developing ionic diode membranes featuring asymmetric structures is in high demand for salinity gradient energy harvesting. These membranes offer benefits in mitigating ion concentration polarization, thereby promoting ion permeability. However, most reported works focus on the role of heterogeneous charge-based bipolar ionic diode membranes for ion concentration polarization suppression, with comparatively less attention given to maintaining ion selectivity. Herein, unipolar ionic diode nanofluidic mesoporous silica membranes featuring stepped mesochannels were developed via a micellar sequential oriented interfacial self-assembly strategy as a salinity gradient energy harvester. Due to the asymmetric mesochannels and unipolar structure (both sides carry negative charge), the ionic diode membranes exhibit a strong rectification ratio of â¼15.91 to facilitate unidirectional ion transport while maintaining excellent cation selectivity (cation transfer number of â¼0.85). Besides, the vertically aligned mesochannels significantly reduce ion transport resistance, generating a high ionic flux. Consequently, the unipolar ionic diode nanofluidic membranes demonstrate a power output of 5.88 W/m2 between artificial sea and river water. The unipolar feature gives notable enhancements of 296% and 144% in power output compared to the symmetric membrane and bipolar ionic diode membrane, respectively. This work opens up new routes for designing ionic diode membranes for salinity gradient energy harvesting.
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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 104. 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.
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Thanks to their excellent photoelectric characteristics to generate cytotoxic reactive oxygen species (ROS) under the light-activation process, TiO2 nanomaterials have shown significant potential in photodynamic therapy (PDT) for solid tumors. Nevertheless, the limited penetration depth of TiO2-based photosensitizers and excitation sources (UV/visible light) for PDT remains a formidable challenge when confronted with complex tumor microenvironments (TMEs). Here, we present a H2O2-driven black TiO2 mesoporous nanomotor with near-infrared (NIR) light absorption capability and autonomous navigation ability, which effectively enhances solid tumor penetration in NIR light-triggered PDT. The nanomotor was rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of a NIR light-responsive black TiO2 nanosphere and an enzyme-modified periodic mesoporous organosilica (PMO) nanorod that wraps around the TiO2 nanosphere. The overexpressed H2O2 can drive the nanomotor in the TME under catalysis of catalase in the PMO domain. By precisely controlling the ratio of TiO2 and PMO compartments in the Janus nanostructure, TiO2&PMO nanomotors can achieve optimal self-propulsive directionality and velocity, enhancing cellular uptake and facilitating deep tumor penetration. Additionally, by the decomposition of endogenous H2O2 within solid tumors, these nanomotors can continuously supply oxygen to enable highly efficient ROS production under the NIR photocatalysis of black TiO2, leading to intensified PDT effects and effective tumor inhibition.
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Raios Infravermelhos , Fotoquimioterapia , Fármacos Fotossensibilizantes , Titânio , Titânio/química , Titânio/farmacologia , Humanos , Porosidade , Animais , Camundongos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Tamanho da PartículaRESUMO
Self-assembly processes triggered by physical or chemical driving forces have been applied to fabricate hierarchical materials with subtle nanostructures. However, various physicochemical processes often interfere with each other, and their precise control has remained a great challenge. Here, in this paper, a rational synthesis of 1D magnetite-chain and mesoporous-silica-nanorod (Fe3O4&mSiO2) branched magnetic nanochains via a physical-chemical coupling coassembly approach is reported. Magnetic-field-induced assembly of magnetite Fe3O4 nanoparticles and isotropic/anisotropic assembly of mesoporous silica are coupled to obtain the delicate 1D branched magnetic mesoporous nanochains. The nanochains with a length of 2-3 µm in length are composed of aligned Fe3O4@mSiO2 nanospheres with a diameter of 150 nm and sticked-out 300 nm long mSiO2 branches. By properly coordinating the multiple assembly processes, the density and length of mSiO2 branches can well be adjusted. Because of the unique rough surface and length in correspondence to bacteria, the designed 1D Fe3O4&mSiO2 branched magnetic nanochains show strong bacterial adhesion and pressuring ability, performing bacterial inhibition over 60% at a low concentration (15 µg mL-1). This cooperative coassembly strategy deepens the understanding of the micro-nanoscale assembly process and lays a foundation for the preparation of the assembly with adjustable surface structures and the subsequent construction of complex multilevel structures.
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Albeit microemulsion systems have emerged as efficient platforms for fabricating tunable nano/microstructures, lack of understanding on the emulsion-interfacial assembly hindered the control of fabrication. Herein, a nucleation-inhibited microemulsion interfacial assembly method is proposed, which deviates from conventional interfacial nucleation approaches, for the synthesis of polydopamine microvesicles (PDA MVs). These PDA MVs exhibit an approximate diameter of 1 µm, showcasing a pliable structure reminiscent of cellular morphology. Through modifications of antibodies on the surface of PDA MVs, their capacity as artificial antigen presentation cells is evaluated. In comparison to solid nanoparticles, PDA MVs with cell-like structures show enhanced T-cell activation, resulting in a 1.5-fold increase in CD25 expression after 1 day and a threefold surge in PD-1 positivity after 7 days. In summary, the research elucidates the influence of nucleation and interfacial assembly in microemulsion polymerization systems, providing a direct synthesis method for MVs and substantiating their effectiveness as artificial antigen-presenting cells.
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Células Apresentadoras de Antígenos , Emulsões , Indóis , Polímeros , Indóis/química , Polímeros/química , Emulsões/química , Células Apresentadoras de Antígenos/imunologia , Humanos , Linfócitos T/imunologiaRESUMO
The encapsulation of functional colloidal nanoparticles (100â nm) into single-crystalline ZSM-5 zeolites, aiming to create uniform core-shell structures, is a highly sought-after yet formidable objective due to significant lattice mismatch and distinct crystallization properties. In this study, we demonstrate the fabrication of a core-shell structured single-crystal zeolite encompassing an Fe3O4 colloidal core via a novel confinement stepwise crystallization methodology. By engineering a confined nanocavity, anchoring nucleation sites, and executing stepwise crystallization, we have successfully encapsulated colloidal nanoparticles (CN) within single-crystal zeolites. These grafted sites, alongside the controlled crystallization process, compel the zeolite seed to nucleate and expand along the Fe3O4 colloidal nanoparticle surface, within a meticulously defined volume (1.5×107≤V≤1.3×108â nm3). Our strategy exhibits versatility and adaptability to an array of zeolites, including but not restricted to ZSM-5, NaA, ZSM-11, and TS-1 with polycrystalline zeolite shell. We highlight the uniformly structured magnetic-nucleus single-crystalline zeolite, which displays pronounced superparamagnetism (14â emu/g) and robust acidity (~0.83â mmol/g). This innovative material has been effectively utilized in a magnetically stabilized bed (MSB) reactor for the dehydration of ethanol, delivering an exceptional conversion rate (98 %), supreme ethylene selectivity (98 %), and superior catalytic endurance (in excess of 100â hours).
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The successful treatment of persistent and recurrent endodontic infections hinges upon the eradication of residual microorganisms within the root canal system, which urgently needs novel drugs to deliver potent yet gentle antimicrobial effects. Antibacterial photodynamic therapy (aPDT) is a promising tool for root canal infection management. Nevertheless, the hypoxic microenvironment within the root canal system significantly limits the efficacy of this treatment. Herein, a nanohybrid drug, Ce6/CaO2/ZIF-8@polyethylenimine (PEI), is developed using a bottom-up strategy to self-supply oxygen for enhanced aPDT. PEI provides a positively charged surface, which enables precise targeting of bacteria. CaO2 reacts with H2O to generate O2, which alleviates the hypoxia in the root canal and serves as a substrate for Ce6 under 660 nm laser irradiation, leading to the successful eradication of planktonic Enterococcus faecalis (E. faecalis) and biofilm in vitro and, moreover, the effective elimination of mature E. faecalis biofilm in situ within the root canal system. This smart design offers a viable alternative for mitigating hypoxia within the root canal system to overcome the restricted efficacy of photosensitizers, providing an exciting prospect for the clinical management of persistent endodontic infection.
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Biofilmes , Cavidade Pulpar , Enterococcus faecalis , Oxigênio , Fotoquimioterapia , Enterococcus faecalis/efeitos dos fármacos , Fotoquimioterapia/métodos , Cavidade Pulpar/microbiologia , Biofilmes/efeitos dos fármacos , Oxigênio/química , Oxigênio/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Polietilenoimina/química , Polietilenoimina/farmacologia , Nanopartículas/química , Animais , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , ClorofilídeosRESUMO
Despite its effectiveness in eliminating cancer cells, ferroptosis is hindered by the high natural antioxidant glutathione (GSH) levels in the tumor microenvironment. Herein, we developed a spatially asymmetric nanoparticle, Fe3O4@DMS&PDA@MnO2-SRF, for enhanced ferroptosis. It consists of two subunits: Fe3O4 nanoparticles coated with dendritic mesoporous silica (DMS) and PDA@MnO2 (PDA: polydopamine) loaded with sorafenib (SRF). The spatial isolation of the Fe3O4@DMS and PDA@MnO2-SRF subunits enhances the synergistic effect between the GSH-scavengers and ferroptosis-related components. First, the increased exposure of the Fe3O4 subunit enhances the Fenton reaction, leading to increased production of reactive oxygen species. Furthermore, the PDA@MnO2-SRF subunit effectively depletes GSH, thereby inducing ferroptosis by the inactivation of glutathione-dependent peroxidases 4. Moreover, the SRF blocks Xc- transport in tumor cells, augmenting GSH depletion capabilities. The dual GSH depletion of the Fe3O4@DMS&PDA@MnO2-SRF significantly weakens the antioxidative system, boosting the chemodynamic performance and leading to increased ferroptosis of tumor cells.
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Ferroptose , Nanopartículas , Neoplasias , Humanos , Compostos de Manganês/farmacologia , Óxidos , Antioxidantes , Glutationa , Dióxido de Silício , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Microambiente TumoralRESUMO
The imitation of mussels and oysters to create high-performance adhesives is a cutting-edge field. The introduction of inorganic fillers is shown to significantly alter the adhesive's properties, yet the potential of mesoporous materials as fillers in adhesives is overlooked. In this study, the first report on the utilization of mesoporous materials in a biomimetic adhesive system is presented. Incorporating mesoporous silica nanoparticles (MSN) profoundly enhances the adhesion of pyrogallol (PG)-polyethylene imine (PEI) adhesive. As the MSN concentration increases, the adhesion strength to glass substrates undergoes an impressive fivefold improvement, reaching an outstanding 2.5 mPa. The adhesive forms an exceptionally strong bond, to the extent that the glass substrate fractures before joint failure. The comprehensive tests involving various polyphenols, polymers, and fillers reveal an intriguing phenomenon-the molecular structure of polyphenols significantly influences adhesive strength. Steric hindrance emerges as a crucial factor, regulating the balance between π-cation and charge interactions, which significantly impacts the multicomponent assembly of polyphenol-PEI-MSN and, consequently, adhesive strength. This groundbreaking research opens new avenues for the development of novel biomimetic materials.
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Materiais Biomiméticos , Bivalves , Animais , Adesivos/química , Materiais Biomiméticos/química , Polímeros/química , VidroRESUMO
The high-current-density Zn-air battery shows big prospects in next-generation energy technologies, while sluggish O2 reaction and diffusion kinetics barricade the applications. Herein, the sequential assembly is innovatively demonstrated for hierarchically mesoporous molybdenum carbides/carbon microspheres with a tunable thickness of mesoporous carbon layers (Meso-Mo2C/C-x, where x represents the thickness). The optimum Meso-Mo2C/C-14 composites (≈2 µm in diameter) are composed of mesoporous nanosheets (≈38 nm in thickness), which possess bilateral mesoporous carbon layers (≈14 nm in thickness), inner Mo2C/C layers (≈8 nm in thickness) with orthorhombic Mo2C nanoparticles (≈2 nm in diameter), a high surface area of ≈426 m2 g-1, and open mesopores (≈6.9 nm in size). Experiments and calculations corroborate the hierarchically mesoporous Mo2C/C can enhance hydrophilicity for supplying sufficient O2, accelerate oxygen reduction kinetics by highly-active Mo2C and N-doped carbon sites, and facilitate O2 diffusion kinetics over hierarchically mesopores. Therefore, Meso-Mo2C/C-14 outputs a high half-wave potential (0.88 V vs RHE) with a low Tafel slope (51 mV dec-1) for oxygen reduction. More significantly, the Zn-air battery delivers an ultrahigh power density (272 mW cm-2), and an unprecedented 100 h stability at a high-current-density condition (100 mA cm-2), which is one of the best performances.
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BACKGROUND: Chemodynamic therapy (CDT) based on Fenton/Fenton-like reaction has emerged as a promising cancer treatment strategy. Yet, the strong anti-oxidation property of tumor microenvironment (TME) caused by endogenous glutathione (GSH) still severely impedes the effectiveness of CDT. Traditional CDT nanoplatforms based on core@shell structure possess inherent interference of different subunits, thus hindering the overall therapeutic efficiency. Consequently, it is urgent to construct a novel structure with isolated functional units and GSH depletion capability to achieve desirable combined CDT therapeutic efficiency. RESULTS: Herein, a surface curvature-induced oriented assembly strategy is proposed to synthesize a sushi-like novel Janus therapeutic nanoplatform which is composed of two functional units, a FeOOH nanospindle serving as CDT subunit and a mSiO2 nanorod serving as drug-loading subunit. The FeOOH CDT subunit is half covered by mSiO2 nanorod along its long axis, forming sushi-like structure. The FeOOH nanospindle is about 400 nm in length and 50 nm in diameter, and the mSiO2 nanorod is about 550 nm in length and 100 nm in diameter. The length and diameter of mSiO2 subunit can be tuned in a wide range while maintaining the sushi-like Janus structure, which is attributed to a Gibbs-free-energy-dominating surface curvature-induced oriented assembly process. In this Janus therapeutic nanoplatform, Fe3+ of FeOOH is firstly reduced to Fe2+ by endogenous GSH, the as-generated Fe2+ then effectively catalyzes overexpressed H2O2 in TME into highly lethal ·OH to achieve efficient CDT. The doxorubicin (DOX) loaded in the mSiO2 subunit can be released to achieve combined chemotherapy. Taking advantage of Fe3+-related GSH depletion, Fe2+-related enhanced ·OH generation, and DOX-induced chemotherapy, the as-synthesized nanoplatform possesses excellent therapeutic efficiency, in vitro eliminating efficiency of tumor cells is as high as ~ 87%. In vivo experiments also show the efficient inhibition of tumor, verifying the synthesized sushi-like Janus nanoparticles as a promising therapeutic nanoplatform. CONCLUSIONS: In general, our work provides a successful paradigm of constructing novel therapeutic nanoplatform to achieve efficient tumor inhibition.
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Nanopartículas Multifuncionais , Neoplasias , Humanos , Peróxido de Hidrogênio , Protocolos de Quimioterapia Combinada Antineoplásica , Doxorrubicina/farmacologia , Glutationa , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
While the nanobio interaction is crucial in determining nanoparticles' in vivo fate, a previous work on investigating nanoparticles' interaction with biological barriers is mainly carried out in a static state. Nanoparticles' fluid dynamics that share non-negligible impacts on their frequency of encountering biological hosts, however, is seldom given attention. Herein, inspired by badmintons' unique aerodynamics, badminton architecture Fe3O4&mPDA (Fe3O4 = magnetite nanoparticle and mPDA = mesoporous polydopamine) Janus nanoparticles have successfully been synthesized based on a steric-induced anisotropic assembly strategy. Due to the "head" Fe3O4 having much larger density than the mPDA "cone", it shows an asymmetric mass distribution, analogous to real badminton. Computational simulations show that nanobadmintons have a stable fluid posture of mPDA cone facing forward, which is opposite to that for the real badminton. The force analysis demonstrates that the badminton-like morphology and mass distribution endow the nanoparticles with a balanced motion around this posture, making its movement in fluid stable. Compared to conventional spherical Fe3O4@mPDA nanoparticles, the Janus nanoparticles with an asymmetric mass distribution have straighter blood flow trails and â¼50% reduced blood vessel wall encountering frequency, thus providing doubled blood half-life and â¼15% lower organ uptakes. This work provides novel methodology for the fabrication of unique nanomaterials, and the correlations between nanoparticle architectures, biofluid dynamics, organ uptake, and blood circulation time are successfully established, providing essential guidance for designing future nanocarriers.
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Nanopartículas , NanoestruturasRESUMO
In recent years, tremendous progress has been made in the development of nanomedicines for advanced therapeutics, yet their unsatisfactory targeting ability hinders the further application of nanomedicines. Nanomaterials undergo a series of processes, from intravenous injection to precise delivery at target sites. Each process faces different or even contradictory requirements for nanoparticles to pass through biological barriers. To overcome biological barriers, researchers have been developing nanomedicines with transformable physicochemical properties in recent years. Physicochemical transformability enables nanomedicines to responsively switch their physicochemical properties, including size, shape, surface charge, etc., thus enabling them to cross a series of biological barriers and achieve maximum delivery efficiency. In this review, we summarize recent developments in nanomedicines with transformable physicochemical properties. First, the biological dilemmas faced by nanomedicines are analyzed. Furthermore, the design and synthesis of nanomaterials with transformable physicochemical properties in terms of size, charge, and shape are summarized. Other switchable physicochemical parameters such as mobility, roughness and mechanical properties, which have been sought after most recently, are also discussed. Finally, the prospects and challenges for nanomedicines with transformable physicochemical properties are highlighted.
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Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Nanopartículas/química , Nanomedicina , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológicoRESUMO
With the promising advances in nanomedicine, numerous strategies have emerged for the diagnosis and treatment of diseases. Among them, enzyme-based multifunctional nanocomposites have attracted a great deal of attention in the field of catalytic biomedicine. These nanocomposites with high catalytic activity are capable of converting low/non-toxic substances into therapeutic ones, thus realizing highly efficient, site-specific therapy with minimal side effects. Enzyme-based nanocomposites for catalytic biomedicine are mainly divided into three types: (i) natural-enzyme based nanocomposites; (ii) artificial-nanozyme based nanocomposites; and (iii) nanocomposites of natural-enzymes and nanozymes. In this review, we discuss key aspects of enzyme-based catalytic biomedicine, including the construction of enzyme-based nanocomposites, their unique properties and applications in catalytic biomedicine. We also highlight the main challenges faced in this field, and provide relevant guidelines for the rational design and extensive application of enzyme-based nanocomposites from our point of view.
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Nanocompostos , Nanoestruturas , Nanomedicina , CatáliseRESUMO
Flexible pressure sensors are widely applied in tactile perception, fingerprint recognition, medical monitoring, human-machine interfaces, and the Internet of Things. Among them, flexible capacitive pressure sensors have the advantages of low energy consumption, slight signal drift, and high response repeatability. However, current research on flexible capacitive pressure sensors focuses on optimizing the dielectric layer for improved sensitivity and pressure response range. Moreover, complicated and time-consuming fabrication methods are commonly applied to generate microstructure dielectric layers. Here, we propose a rapid and straightforward fabrication approach to prototyping flexible capacitive pressure sensors based on porous electrodes. Laser-induced graphene (LIG) is produced on both sides of the polyimide paper, resulting in paired compressible electrodes with 3D porous structures. When the elastic LIG electrodes are compressed, the effective electrode area, the relative distance between electrodes, and the dielectric property vary accordingly, thereby generating a sensitive pressure sensor in a relatively large working range (0-9.6 kPa). The sensitivity of the sensor is up to 7.71%/kPa-1, and it can detect pressure as small as 10 Pa. The simple and robust structure allows the sensor to produce quick and repeatable responses. Our pressure sensor exhibits broad potential in practical applications in health monitoring, given its outstanding comprehensive performance combined with its simple and quick fabrication method.
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Grafite , Humanos , Porosidade , EletrodosRESUMO
Although there has been intense research on plasmon-induced charge transfer within metal/semiconductor heterostructures, previous studies have all focused on the surface plasmonic resonance (SPR) of only noble metals. Herein and for the first time, we observe and take into account the plasmonic coupling between SPR of both noble-metal and semiconductor nanostructures. A W18O49/Ag heterostructure composed of metallic Ag nanoparticles (Ag NPs) and semiconducting W18O49 nanowires (W18O49 NWs) is designed and fabricated, which exhibits a broad and strong SPR absorption in the visible wavelength range. This SPR band is attributed to the SPR coupling between the SPR of both Ag NPs and W18O49 NWs. Surface-enhanced Raman scattering (SERS) is then used to reveal the interactions between the metal SPR, semiconductor SPR, and the heterostructure's charge transfer (CT) process, demonstrating that such coupled SPR enhanced the heterostructure's internal CT and SERS signals. Finally, we proposed a new coupled-plasmon-induced charge transfer mechanism to interpret the improved CT efficiency between the SERS substrate and molecules. Our work provides insight for further studies on plasmonic effects and interfacial charge transfer in metal/semiconductor heterostructures.
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The ability of Janus nanoparticles to establish biological logic systems has been widely exploited, yet conventional non/uni-porous Janus nanoparticles are unable to fully mimic biological communications. Here we demonstrate an emulsion-oriented assembly approach for the fabrication of highly uniform Janus double-spherical MSN&mPDA (MSN, mesoporous silica nanoparticle; mPDA, mesoporous polydopamine) nanoparticles. The delicate Janus nanoparticle possesses a spherical MSN with a diameter of ~150 nm and an mPDA hemisphere with a diameter of ~120 nm. In addition, the mesopore size in the MSN compartment is tunable from ~3 to ~25 nm, while those in the mPDA compartments range from ~5 to ~50 nm. Due to the different chemical properties and mesopore sizes in the two compartments, we achieve selective loading of guests in different compartments, and successfully establish single-particle-level biological logic gates. The dual-mesoporous structure enables consecutive valve-opening and matter-releasing reactions within one single nanoparticle, facilitating the design of single-particle-level logic systems.
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Nanopartículas , Emulsões , Nanopartículas/química , Compostos de Diazônio , Piridinas , Dióxido de Silício/química , PorosidadeRESUMO
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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A sulfhydryl monomicelles interfacial assembly strategy is presented for the synthesis of fully exposed single-atom-layer Pt clusters on 2D mesoporous TiO2 (SAL-Pt@mTiO2 ) nanosheets. This synthesis features the introduction of the sulfhydryl group in monomicelles to finely realize the controllable co-assembly process of Pt precursors within ordered mesostructures. The resultant SAL-Pt@mTiO2 shows uniform SAL Pt clusters (≈1.2â nm) anchored in ultrathin 2D nanosheets (≈7â nm) with a high surface area (139â m2 g-1 ), a large pore size (≈25â nm) and a high dispersion (≈99 %). Moreover, this strategy is universal for the synthesis of other SAL metal clusters (Pd and Au) on 2D mTiO2 with high exposure and accessibility. When used as a catalyst for hydrogenation of 4-nitrostyrene, the SAL-Pt@mTiO2 shows a high catalytic activity (TOF up to 2424â h-1 ), 100 % selectivity for 4-aminostyrene, good stability, and anti-resistance to thiourea poisoning under relatively mild conditions (25 °C, 10â bar).