Core-shell Hybrid Research Articles

Hierarchical porous CS@Ce-MnO2 as cathode for energy-dense and long-cycling flexible aqueous zinc-ion batteries

Aqueous zinc-ion batteries (ZIBs) have been considered one of the most promising flexible chemical power sources, because of their affordable cost, absolute security, and lightweight. However, the development of flexible aqueous ZIBs has been hindered by cathode materials due to their unsatisfied capacity, unstable structure, and ambiguous electrochemical energy storage mechanism. To address the above issues, a high-performance manganese cerium-doped dioxide-based core–shell hybrid structure cathode (CS@Ce-MnO2) has been successfully prepared via a facile low-temperature liquid-phase reaction strategy. Benefit from the delicately designed hierarchical carbon spheres core and cerium-doped manganese dioxide nanosheets shell structure, the capacity and stability of CS@Ce-MnO2 based flexible ZIBs has been dramatically improved, and the origin of the improved electrochemical performance and storage mechanism was demonstrated by electrochemical methods and ex-site x-ray diffraction (XRD) and scanning electron microscopy (SEM). The principal reason for the high reversible specific capacity is the plausible Zn2+ and H+co-insertion/extraction, while the porous structure of the carbon spheres contributes to the improved electron conduction and ion transport in the MnO2 matrix. This work provides a new opportunity for high-performance flexible aqueous zinc-ion batteries.

The mega-merger strategy: M@COF core-shell hybrid materials for facilitating CO2 capture and conversion to monocyclic and polycyclic carbonates

Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) have garnered significant attention for their potential in CO2 capture and conversion, owing to their unique properties. However, these materials suffer from inherent drawbacks such as poor stability and catalytic activity, leading to unsatisfactory utilization efficiency. In this work, we fabricated a series of novel M@COF hybrid materials by growing pyridine-based COFs with varying thicknesses on NH2-UiO-66 cores. These materials exhibited large specific surface areas and favorable chemical stability. The combination of the high specific surface area of MOF and the multiple interacting π-π stacking interactions of COF in these M@COF hybrid materials resulted in significantly enhanced CO2 adsorption performance, surpassing that of individual parent MOF or COF. In addition, an ion-functionalized M@COF-0.15-Br was fabricated through a simple post-synthesis modification. The presence of abundant ion active sites and interfacial synergistic effects in M@COF-0.15-Br effectively facilitated activation of reactants, enabling efficient catalytic conversion of CO2 to monocyclic and polycyclic carbonates. Consequently, the superior CO2 capture and conversion achieved using this M@COF core-shell hybrid material offers a new approach to design advanced functional materials with optimized structures for CO2 capture and conversion.

Electrospun natural melanin nanoparticles on polyvinyl alcohol nanofiber hybrid meshes: Processing and crosslinking optimization

Hybrid systems consisting the combination of nanofibers and nanoparticles provide great benefits for nanotechnology and its theranostic applications. Herein, a hybrid system incorporates natural melanin nanoparticles (MNPs) and polyvinyl alcohol (PVA) based nanofibers was introduced using electrospinning method by taking account the effects of viscosity and conductivity of MNP and PVA solutions along with the potential physicochemical effects of crosslinking on the process. Monolithic and core-shell hybrid substances were designed using single and coaxial nozzles at different voltage and flow rates. Scanning electron microscopy (SEM) images were employed for the evaluation of the nanofiber morphology to acquire optimized parameters of the electrospinning process. SEM analysis indicated that the diameters of monolithic and core-shell nanoparticle-nanofiber hybrids were 304 ± 88 nm and 465 ± 56 nm, respectively, depending on the nozzle type. Additionally, nanofibers were assessed in terms of mechanical strength and compatibility between MNPs and PVA. The stability of nanofibers was enhanced with solution crosslinking by considering swelling, degradation rates and in vitro release kinetics of MNPs. The most promising monolithic nanofibers were obtained at a ratio of 7:3 (PVA:MNP) and 10–30 min of crosslinking yielded stable nanofibers after interaction with water. ATR-FTIR spectrum analysis showed that compatibility in monolithic and core-shell nanofibers was rendered by hydrogen bonds between OH in PVA and –NH2/−OH in MNPs. As a result of the crosslinking process, the nanofibers gained better swelling and less degradable properties, thus no MNP release occurred from the matrix. As another notable point, compared to monolithic and non-crosslinked nanofibers, core-shell and crosslinked nanofibers presented stronger mechanical properties. Consequently, an optimization study incorporating both crosslinking and electrospinning methods was conducted to obtain MNPs and PVA based nanofibers for applications with green, sustainable, multifunctional and photoactive substances in biomedical engineering.

Self-Assembly of Core-Shell Hybrid Nanoparticles by Directional Crystallization of Grafted Polymers.

Nanoparticle self-assembly is an efficient bottom-up strategy for the creation of nanostructures. In a typical approach, ligands are grafted onto the surfaces of nanoparticles to improve the dispersion stability and control interparticle interactions. Ligands then remain secondary and usually are not expected to order significantly during superstructure formation. Here, we investigate how ligands can play a more decisive role in the formation of anisotropic inorganic-organic hybrid materials. We graft poly(2-iso-propyl-2-oxazoline) (PiPrOx) as a crystallizable shell onto SiO2 nanoparticles. By varying the PiPrOx grafting density, both solution stability and nanoparticle aggregation behavior can be controlled. Upon prolonged heating, anisotropic nanostructures form in conjunction with the crystallization of the ligands. Self-assembly of hybrid PiPrOx@SiO2 (shell@core) nanoparticles proceeds in two steps: First, the rapid formation of amorphous aggregates occurs via gelation, mediated by the interaction between nanoparticles through grafted polymer chains. As a second step, slow radial growth of fibers was observed via directional crystallization, governed by the incorporation of crystalline ribbons formed from free polymeric ligands in combination with crystallization of the covalently attached ligand shell. Our work reveals how crystallization-driven self-assembly of ligands can create intricate hybrid nanostructures.

Core-shell iron oxide-platinium@metal organic framework/epirubicin nanospheres: Synthesis, characterization and anti-breast cancer activity

Potential cancer therapy can be accomplished by utilizing nano-based platforms that supply facilitated drug penetration inside cancer cells. In this paper, an intelligent therapeutic nano-based system derived from metal–organic framework (MOF) core–shell hybrids with the capacity of potential drug loading, tumor microenvironment-triggered drug release as well as promising cell penetration was developed. The core–shell iron oxide-platinium@MOF/epirubicin (Fe3O4-Pt@MOF/EPI) nanospheres were constructed, where these nanoplatforms endow the system with the capability of pH-responsive drug release. The synthesized Fe3O4-Pt@MOF/EPI nanoparticles were characterized using different well-known techniques. The Fe3O4-Pt@MOF/EPI nanospheres were shown to have a dried size of around 50 nm (evidenced by SEM analysis), a spherical/core–shell/porous structure (evidenced by TEM), and an average hydrodynamic size of 92.89 nm (evidenced by DLS). Additionally, TGA analysis revealed that Fe3O4-Pt@MOF/EPI nanospheres had a weight loss at temperatures between 220 and 450 °C associated with the removal of MOF and EPI from the structure of core–shell nanospheres. The N2 adsorption–desorption data also reflected the porosity of core–shell Fe3O4-Pt@MOF nanospheres by indicating type IV behavior with an apparent hysteresis loop in the range of 0.38–0.98. Furthermore, XRD analysis disclosed the changes in the peak intensity at positions of 57.2° and 39.5°, which indicated the effects of loaded MOF on Fe3O4-Pt nanosphere. Moreover, core–shell Fe3O4-Pt@MOF/EPI nanospheres showed high loading capacity and drug release in a pH-responsive manner. Cell viability and cellular uptake assays on mouse fibroblast (NIH3T3) and triple-negative 4 T1 breast (TNFB) tumors showed that the core–shell Fe3O4-Pt@MOF/EPI nanospheres effectively inhibited TNFB cancer cells proliferation through inducing higher cell penetration compared to free EPI while having good biocompatibility against NIH3T3 cells. In conclusion, the present study may provide useful information about the development of efficient anticancer platforms against breast cancer cells, while further in vivo and pre-clinical assays are required to support this study.

Clickable periodic mesoporous organosilicas core-shell particles with radially-oriented mesopores for high-performance liquid chromatography

It is important to explore well-defined materials to further improve the performance of chromatographic stationary phase. Periodic mesoporous organosilica (PMO) with uniform-distributed organic functionalities and high chemical stability is rising star of chromatography. In this work, ethylene-bridged PMO with excellent organization over distances of several dozen nm was coated on silica cores to form core-shell particles with radially-oriented mesopores. The separation performance for naphthalene was 9.7 × 104 plates/m after derivatization of the C18 group on the terminal vinyl of vinyltriethoxysilane by “thiol-ene” click reaction. These hybrid core-shell particles had good mechanical strength, as well as adequate chemical stability (0.1%TEA, pH 9.5), so it has the potential for HPLC separation.

Construction of core–shell MOF@COF hybrid materials as highly efficient light-responsive oxidase-like nanozymes for colorimetric detection of glutathione

In this work, a novel and light-responsive nanozyme, with enzyme-like characteristics, was synthesized based on core–shell MOF@COF hybrid materials. The donor–acceptor type COF (as shell) synthesized by 1,3,6,8-tetrakis(4-aminophenyl)pyrene (Py, donor) and thieno[3,2-b]thiophene-2,5-dicarbaldehyde (Tt, acceptor) was wrapped on the NH2-Cu-MOF (robust catalyst, as core) through a sequential growth strategy. Surprisingly, with visible-light irradiation, the core–shell Cu-MOF@Py-Tt hybrid materials exhibited extremely high oxidase-like enzymatic catalytic activity attributing to the high separation efficiency of photogenerated carriers in core–shell hybrid materials and the shell with the characteristics of large π-conjugated and D-A electronic structure. With the light-control catalytic activity, Cu-MOF@Py-Tt can form the O2•- that can catalyze the TMB to blue color. Consequently, a light-control, sensitive and rapid colorimetric method for determination of glutathione (GSH) was designed based on light-responsive oxidase mimic of core–shell Cu-MOF@Py-Tt with the linear range of 0.2–70 μM and limit of detection of 0.17 μM. The proposed method demonstrated the future potential of core–shell MOF@COF hybrid materials to obtain excellent nanozyme activity.

Multifunctional electrochromic hybrid PANI@WO3 core-shell for energy generation and storage

Materials that can be deposited easily and shows multifunctional application are always in demand. Two technologically important materials, polyaniline (PANI) and tungsten trioxide (WO3) have been amalgamated using an uncommon, yet simple, technique of deposition, chronoamperometry to obtain a hybrid core-shell structure and its application in three different areas of electrochromic display, electrocatalysis and energy storage has been investigated. Electrodepositing WO3 and PANI onto highly conducting substrates one on top of other, resulted in formation of PANI (shell), WO3 (Core) (PANI@WO3) electrode resulting in a highly uniform fibrous surface structure. Electrochemistry performed using the conventional three electrode step up suggested a very good charge storing capacity, stability also indicating a pseudo capacitive nature which was later confirmed with the help of Nyquist plot. Besides very good values of areal capacitance (855 mF/cm2), power density (6.5 kW/cm2) and energy density (1.09 kWh/cm2) established its supercapacitive performance. Next, its behaviour as an electrocatalyst was studied by duly plotting polarisation curves and their corresponding Tafel plots. The PANI@WO3 electrode deposited on a transparent electrode exhibited green-blue-yellow-transparent color switching under different bias conditions with a very small voltage of 0.5 V. A fast switching of 0.4 s and a great color contrast of ∼50 % in visible as well IR region were displayed making the electrochemically deposited core-shell a good candidate for multifunctional application in energy generation, storage with an inerrability with smart electrochromic windows.

Stability Criterion for the Assembly of Core-Shell Lipid-Polymer-Nucleic Acid Nanoparticles.

Hybrid core-shell lipid-polycation-nucleic acid nanoparticles (LPNPs) provide unique delivery strategies for nonviral gene therapeutics. Since LPNPs consist of multiple components, involving different pairwise interactions between them, they are challenging to characterize and understand. Here, we propose a method based on fluorescence cross-correlation spectroscopy to elucidate the association between the three LPNP components. Through this lens, we demonstrate that cationic lipid shells (liposomes) do not displace polycations or DNA from the polycation-DNA cores (polyplexes). Hence, polyplexes and liposomes must be oppositely charged to associate into LPNPs. Furthermore, we identify the liposome:polyplex number ratio (ρN), which was hitherto an intangible quantity, as the primary parameter predicting stable LPNPs. We establish that ρN ≥ 1 ensures that every polyplex is enveloped by a liposome, thus avoiding coexisting oppositely charged species prone to aggregation.

Synthesis and Raman Performance Enhancement of Multilayer AuAg Heterostructures with Magnetic Resonance

Significant amplification of surface enhanced Raman scattering (SERS) signals can be achieved mainly by the electric field enhancement in metal core-shell nanostructures, and the enhanced magnetic field is rarely studied. In this study, we prepared multi-gap Au/AgAu core-shell hybrid nanostructures by using gold nanocup as the core. The overgrowth processes to grow one, two, and three layers of AgAu hybrid nanoshells can produce Au/AgAu1, Au/AgAu2, and Au/AgAu3 heteronanostructures. The strong plasmon coupling between the core and shell leads to significant electromagnetic field enhancement. Under the synergistic effect of electromagnetic plasmon resonance and plasmon coupling, Au/AgAu core-shell hybrid nanostructures exhibit excellent SERS signals. We also investigate the effect of the interstitial position of the rhodamine B (RhB) molecule on Raman enhancement in Au/AgAu3 heteronanostructures. This study can provide new ideas for the synthesis of multi-gap Raman signal amplifiers based on magnetic plasmon coupling.

Ultrastable and high-performance 3D core-shell NiCo2S4@Bi2O3 nanorod arrays as anode for Li[sbnd]S batteries

In spite of the low specific capacity of Bi2O3 (∼386 mA h g−1), it lies among auspicious contenders to be utilized as anode for future generation lithium-ion batteries (LIBs). Conversely, the persistently low valued capacity is causing the restrictions on its superb anticipated electro-chemical properties and obscuring their useful applications/devices. Similarly bimetallic transition metal sulfides with superior electro-chemical performances have gained the attention due to the existence of synergistic effect among bimetallic cations. Herein, a novel template-assisted, two-step hydrothermal method followed by electrodeposition technique is employed to fabricate hybrid 3D core-shell NiCo2S4@Bi2O3 nanorod arrays (NRAs). The fabricated hybrid-structure comprises the qualities of both materials; NiCo2S4 presents the backbone for structural stability, while Bi2O3 provides the high specific capacity. Hybrid core-shell structure has provided the integrating facile strain relaxation, along with the fast electron and ion transport. Hybrid 3D core-shell NiCo2S4@Bi2O3 NRAs with the possession of high Bi2O3 mass loading has exhibited the excellent capacity of ∼2344 mA h g−1 with a columbic efficiency of 96 %, which is much improved compare to pristine NiCo2S4 NRAs (∼1865 mA h g−1) with columbic efficiency of 89 % and Bi2O3 nanosheet arrays (∼1160 mA h g−1) with columbic efficiency of 54 % respectively, demonstrating that hybrid 3D core-shell NiCo2S4@Bi2O3 NRAs have presented decent rate capability at current density 0.4 A g−1 and particularly significant cycle stability (∼1930 mA h g−1) even after 100 successive cycles. Achieved outcomes not only highlight the innovative opportunity for novel core-shell formation, but also provide the vision of rational design for innovative electrode materials for LIBs.

Next-generation ecofriendly MR fluid: Hybrid GO/ Fe2O3 encapsulated carbonyl iron microparticles with improved magnetorheological, tribological, and corrosion resistance properties

In this study, magnetorheological fluid (MRF) was developed using hybrid core-shell particles. The core of these particles consists of carbonyl iron (CI), while the shell is composed of graphene oxide (GO) and iron oxide (Fe2O3) nanocomposite particles. The hybrid nanocomposite and core-shell particles were synthesized through a simple wet stirring process. A blended biocompatible oil comprising 90% rice bran oil and 10% silicone oil was employed as the continuous phase to ensure environmental and economic feasibility. Various characterization techniques were employed to examine the surface, structural, and magnetic properties of the hybrid core-shell particles. Magnetorheological (MR) measurements demonstrated that the incorporation of GO/Fe2O3 nanocomposite particles onto the CI particles (CIPs) significantly enhanced the shear stress and yield stress properties of the resulting MRF. This improvement can be ascribed to an increase in the magnetic saturation resulting from the encapsulation of GO-decorated Fe2O3 nanocomposite particles. The corrosion resistance and sedimentation properties were evaluated in this study, and the hybrid core-shell particles exhibited superior results compared to the bare CIPs. In terms of tribological performance, the hybrid core-shell particles exhibited significant improvement in friction and wear properties in comparison to the bare CIPs-based MRF and dry sliding condition. The significant reduction in coefficient of friction (COF) and wear might be attributed to the development of a lubricating protective layer consisting of bare CIPs and hybrid core-shell particles-based MR fluids (MRFs) at the contact interface. Consequently, this study offers an economical and effective approach for formulating MRFs with desirable rheological and tribological characteristics and corrosion inhibition properties, making them suitable for various environmental and industrial applications.

Core–shell bimetallic copper–molybdenum sulfides nanomaterials derived from a Cu-based metal-organic framework as efficient bifunctional electrocatalyts

The critical depletion of fossil fuels and the alarming increase in environmental pollution highlight the urgent need to develop efficient and durable electrocatalysts to produce renewable energy. We propose a hydrothermal synthesis of a CuxS@MoS2 core–shell hybrid electrocatalyst with enhanced catalytic activity for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Utilizing Cu-BTC as a template, our proposed hydrothermal synthesis results in a unique core–shell morphology comprising bimetallic metal sulfide components. This configuration effectively expands the electrochemically active surface area, enhancing charge transfer kinetics and improving catalytic activity. The optimized CuxS@MoS2 electrocatalyst presents low overpotentials of 141 and 334 mV for the OER and HER, respectively, achieving a current density of 10 mA cm−2. This novel synthesis offers a feasible strategy for the preparation of high-efficiency core–shell bimetallic metal sulfide nanomaterials suitable for application in various fields such as energy conversion and storage.

Triphasic Ni2P−Fe2P−CoP heterostructure interfaces for efficient overall water splitting powered by solar energy

In this study, we design a triphasic Ni2P − Fe2P − CoP heterostructure appearing under the form of a hierarchical 3D core–shell hybrid (CoP@Ni2P − Fe2P) for bifunctionally catalyzing both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline medium. Density functional theory results indicate that the rich interfaces of Ni2P − Fe2P − CoP architecture exhibit the best electronic properties and enhanced multiple electroactive site number with optimum hydrogen adsorption energy, significantly surpassing the CoP, CoP−Ni2P, or CoP−Fe2P cases. Therefore, the electrolyzer cell of CoP@Ni2P − Fe2P(+,−) requires a small operating voltage of 1.51 V to reach 10 mA cm−2 during alkaline water splitting, outperforming the commercial catalyst couple of Pt/C(−)//RuO2(+) and numerous earlier reports. In addition, the solar-driven water splitting system demonstrates a high solar-to-hydrogen (STH) conversion of 15.33 %, along with excellent long-term stability. The results open a potential approach to design innovative high-performance electrocatalysts for practical green hydrogen production via electrochemical water splitting process.

Tetracycline Removal through the Synergy of Catalysis and Photocatalysis by Novel NaYF4:Yb,Tm@TiO2-Acetylacetone Hybrid Core-Shell Structures.

Novel hybrid core-shell structures, in which up-converting (UC) NaYF4:Yb,Tm core converts near-infrared (NIR) to visible (Vis) light via multiphoton up-conversion processes, while anatase TiO2-acetylacetonate (TiO2-Acac) shell ensures absorption of the Vis light through direct injection of excited electrons from the highest-occupied-molecular-orbital (HOMO) of Acac into the TiO2 conduction band (CB), were successfully synthesized by a two-step wet chemical route. Synthesized NaYF4:Yb,Tm@TiO2-Acac powders were characterized by X-ray powder diffraction, thermogravimetric analysis, scanning and transmission electron microscopy, diffuse-reflectance spectroscopy, Fourier transform infrared spectroscopy, and photoluminescence emission measurement. Tetracycline, as a model drug, was used to investigate the photocatalytic efficiencies of the core-shell structures under irradiation of reduced power Vis and NIR spectra. It was shown that the removal of tetracycline is accompanied by the formation of intermediates, which formed immediately after bringing the drug into contact with the novel hybrid core-shell structures. As a result, ~80% of tetracycline is removed from the solution after 6 h.

Ceramic Open Cell Foams Featuring Plasmonic Hybrid Metal Nanoparticles for In Situ SERS Monitoring of Catalytic Reactions

AbstractThis work presents porous zirconia‐toughened alumina ceramics functionalized with Au@Pd/Au@Pt core–shell nanoparticle (NP) for in situ monitoring of catalytic reactions via surface‐enhanced Raman scattering (SERS) which is augmented by the open cell foam structure of the ceramic support. In this respect, the porous ceramic enables efficient light trapping and propagation onto the coated surface, which provides good accessibility of the catalyst, while the core–shell particles are equipped with a catalytically active shell and a plasmonic core which enables SERS sensing. The metallic hybrid core–shell NPs are synthesized by the Au‐seed mediated method and colloidally deposited onto the open porous ceramic matrix prepared via the polymer replica method. The Au@Pt NP functionalized porous ceramic show a Raman enhancement factor up to 106, which is significantly higher than that of non‐porous samples. In situ reaction monitoring via SERS is demonstrated by the Pt‐catalyzed reduction of 4‐nitrothiophenol to 4‐aminothiophenol, showing high specificity for analysis of reactants and products. This multifunctional material concept featuring ceramics‐augmented SERS and catalytic activity could be extended beyond real‐time, sensitive reaction monitoring toward high temperature reactions, photothermal catalysis, bioprocessing and ‐sensing, green energy conversion, and related applications.

Self-assembled morphology-controlled hierarchical Fe3O4 @LDH for Cr(VI) removal

The efficient removal of Cr(VI) in water with high solubility and mobility is of great significance because Cr(VI) is one of the most toxic heavy metals, but it also faces some major challenges. The dispersibility and recyclability of nanoadsorbents are closely related to their Cr(VI) removal efficiency. Herein, the self-assembly method was used to synthesize core-shell hybrid nanoparticles, named Fe3O4 @LDH, with a vertically aligned layered double hydroxide (MgAl-LDH) nanosheet shell and a Fe3O4 magnetite core. The obtained Fe3O4 @LDH nanoparticles exhibit a highly porous and well-ordered three-dimensional core-shell structure with a wool-ball-like morphology. The self-assembled morphology of the core-shell structure can be effectively controlled and induced by regulating the Mg2+/Al3+ ratio of the reaction system. The influence mechanism of charge density of LDH brucite-like layers on the self-assembled morphology was proposed. Fe3O4 @LDH nanoparticles exhibit a Cr(VI) adsorption capacity of 108.7 mg/g. The synergetic contribution of the hybrid self-assembly of Fe3O4 and MgAl-LDH leads to more dispersion, better adsorption capability, and faster kinetics. Moreover, because of the super-paramagnetic and highly saturated magnetization (34.53 emu/g) of the Fe3O4 @LDH nanoparticles, they can be used as efficient magnetic adsorbents and easily separated using a magnetic field and reused. The prepared Fe3O4 @LDH nanoparticles are a cost-effective nanoadsorbent for removing Cr(VI) from wastewater and provide a reference for the structural design and construction of nanocomposites.

Separation and purification of target flavonoids using covalently connected MOFs@boronic acid-functionalized-COFs magnetic hybrids: Precise identification and enhanced stability

The magnetic boronate based sorbents have been widely used to separation of cis-diol containing flavonoids. However, It's still challenging due to its chemical structural fragility and low grafting efficiency. The major obstacles are low concentration, the hydrophobicity of flavoniods, and complexity of crude extract solutions. For solving these problems, a new kind of covalently connect MOF@boronic acid-functionalized-COFs core–shell hybrid composites based on magnetic colloidal nanocrystal clusters (MCNCs), MCNCs@NH2-UiO-66@BTCA-BA-COFs, with high surface area, abundant binding sites and excellent chemical and structurally stability were synthesized for enhancing the structure stability and selective recognition efficiency. The alkynylation COFs were not only to be facilely grated on the surface of magnetic microsphere@NH2-UiO-66 via Schiff-based reaction but also beneficial to the further modification of azide phenylboronic acid group via click reaction. Such mentioned advantages and covalently connect click strategy could generate highly structure stable and strong binding sites for the template flavonoids (Naringin, NRG). Adsorption equilibrium experiments were reached rapidly within 120 min, and the maximum equilibrium binding capacities of MCNCs@PDA@NH2-UiO-66@BTCA-BA-COFs were 31.20 µmol g−1 for NRG. Moreover, MCNCs@PDA@NH2-UiO-66@BTCA-BA-COFs exhibited a stronger selectivity towards NRG than other competitive targets (i.e rutin, catechol, hesperetin, o-nitrophenol). The MCNCs@PDA@NH2-UiO-66@BTCA-BA-COFs have shown outstanding reusability of 91.99 % loss in enrichment performance towards NRG after seven times repeatedly. The obtained MCNCs@PDA@NH2-UiO-66@BTCA-BA-COFs-based mass spectrum (MS) methods were applied to analyze the purity of NRG products. As excepted, a commercially available NRG with purity (approximately 60 %) could be effectively extracted and concentrated to 93.15 % purity. More interestingly, the separation performance of the sorbents was influenced by hydrophilic and hydrophobic performance. This approach provided an idea for constructing a new kind of hybrid sorbents with both enhanced functionality, suitable hydrophobic performance and fast magnetic-response behavior, which is of great significance to the field of separation and purification of hydrophobic flavonoids.

Novel preparation of nano-SiO2 core-shell hybrid inorganic-organic sizing agents for enhanced interfacial and mechanical properties of carbon fibers/epoxy composites

The interfacial properties of carbon fibers (CFs) composites were improved by modifying the self-emulsifying amphiphilic epoxy sizing agent with nano-SiO2 particles. Herein, a series of inorganic–organic nano-SiO2 core-cationic epoxy shell hybrid sizing agents (referred to as nano-SiO2 core–shell hybrid sizing agents) with various nano-SiO2 contents were synthesized and used to enhance the mechanical properties of CF/EP. The study indicated that the nano-SiO2 core–shell hybrid sizing agents had the characteristics of the perfect core–shell structure, single dispersion, particle sizes controllable, good storage and high heat resistance. Nano-SiO2 core–shell hybrid sizing agents significantly increased the surface roughness and the surface energy of CFs compared to the unmodified sizing agent. Nano-SiO2 core–shell hybrid sizing agents (7.2% SiO2) increased ILSS, IFSS by 16.92%, 21% and nano-SiO2 core–shell hybrid sizing agents (5.8% SiO2) increased tensile force of monofilament CF by 23.78%, respectively, compared with the unmodified agent. These reinforcements may have been caused by the enhancement of the stress transference of nano-particles in the interface between CFs and EP through an interlocking mechanism. As a result, the nano-SiO2 core–shell sizing agent overcomes the lack of adhesion of traditional nano modification methods and shows remarkable adhesion properties.

ZnO@C Microballs Wrapped with Ni(OH)2 Nanofilms for Electrochemical Sensing of Glucose and Hydrogen Peroxide.

Tailor-made metal oxide/hydroxide core-shell structures are promising for the fabrication of effective electrocatalysts. Here, we report the development of a core-shell structure based on carbon-doped and Ni(OH)2 nanofilms wrapped ZnO microballs (NFs-Ni(OH)2 /ZnO@C MBs) for glucose and hydrogen peroxide (H2 O2 ) monitoring. The unique ball-like morphology of the designed structure is achieved through a facile solvothermal strategy by the control of reaction conditions. Typically, ZnO@C MBs offer highly conductive core, and the shell of Ni(OH)2 nanofilms increases the density of catalytic active sites. The interesting morphology and the brilliant electrocatalytic efficacy of designed hybrid, encourage us to design a multi-mode sensor for glucose and H2 O2 screening. The NFs-Ni(OH)2 /ZnO@C MBs/GCE glucose sensor presented good sensitivities (647.899 & 161.550 μA (mmol L-1 )-1 cm-2 ), a quick response (<4 s), lower limit of detection (0.04 μmol L-1 ), and wide detection range (0.004-1.13 & 1.13-5.02 mmol L-1 ). Similarly, the same electrode revealed excellent H2 O2 sensing features including good sensitivities, two linear parts of 3.5-452 and 452-1374 μmol L-1 , and detection limit of 0.03 μmol L-1 as well as high selectivity. Thus, the development of novel hybrid core-shell structure is useful for potential applications in glucose and H2 O2 screening from environmental and physiological samples.