Interplay of Properties and Functions upon Introduction of Mesoporosity in ITQ‐4 Zeolite

The introduction of mesoporosity in zeolites is often directly coupled to changes in their overall catalytic performance without the detailed assessment of other key functions required for the rational design of the catalytic process such as accessibility, adsorption, and transport. This study presents an integrated approach to study property–function relationships in hierarchical zeolites. Accordingly, desilication of the 1D ITQ‐4 zeolite in alkaline medium is applied to develop different degrees of mesoporosity. Along with porosity modification, significant changes in composition, structure, and acidity occur. Relationships are established between the physicochemical properties of the zeolites and their characteristics in the adsorption and elution of light hydrocarbons (C₂ to C₅, alkanes and alkenes) as well as in the catalytic activity in low‐density polyethylene (LDPE) pyrolysis. The recently introduced hierarchy factor can appropriately relate porosity changes to catalytic performance.     

Defect Creation in HKUST‐1 via Molecular Imprinting: Attaining Anionic Framework Property and Mesoporosity for Cation Exchange Applications

Discovering new methods to tailor the physical and chemical properties of metal–organic frameworks (MOFs) for their numerous potential applications is highly desired. In this work, engineering defects in MOF via a molecular imprinting approach is developed to endow HKUST‐1, a well‐studied classical MOF, with hierarchical structure, mesoporosity, and anionic framework property. Ringlike anionic HKUST‐1 (HKUST‐1‐R) and a wide variety of metal‐doped isostructural analogues (M/HKUST‐1‐R, M = Ca, Cd, Ce, Co, Li, Mn, Na, Ni, or Zn) are obtained. The benefits of transforming imprinted HKUST‐1‐R to M/HKUST‐1‐R are further demonstrated for various applications. This synthetic strategy is therefore suitable for rational design and functionalization of MOFs in addition to their morphological control in nanoscale.     

Hierarchical FAU‐ and LTA‐Type Zeolites by Post‐Synthetic Design: A New Generation of Highly Efficient Base Catalysts

Hierarchical FAU‐ and LTA‐type catalysts are prepared by post‐synthetic modifications and evaluated in the base‐catalyzed Knoevenagel condensation of benzaldehyde with malononitrile. A novel route to attain mesoporous Al‐rich zeolites (A and X) is demonstrated, while mesoporous Y and USY zeolites are prepared using recently developed methods. Base functionality is introduced by alkali ion exchange (Cs, Na) or by high‐temperature nitridation in ammonia. A thorough characterization of the zeolites' structure, composition, porosity, morphology, and basicity demonstrates that the presence of a secondary mesopore network enhances the ion‐exchange efficiency and the structural incorporation of nitrogen. The modified USY zeolites display twice the conversion, while the hierarchical A, X, and Y are up to 10 times more active based on the enhanced accessibility. These results demonstrate that the Knoevenagel condensation takes place predominately at the external surface, highlighting secondary porosity as a key criterion in the design of basic zeolite catalysts.     

A Novel Conductive Core–Shell Particle Based on Liquid Metal for Fabricating Real‐Time Self‐Repairing Flexible Circuits

As a critical part of flexible electronics, flexible circuits inevitably work in a dynamic state, which causes electrical deterioration of brittle conductive materials (i.e., Cu, Ag, ITO). Recently, gallium‐based liquid metal particles (LMPs) with electrical stability and self‐repairing have been studied to replace brittle materials owing to their low modulus and excellent conductivity. However, LMP‐coated Ga₂O₃ needs to activate by external sintering, which makes it more complicated to fabricate and gives it a larger short‐circuit risk. Core–shell structural particles (Ag@LMPs) that exhibit excellent initial conductivity(8.0 Ω sq^?1) without extra sintering are successfully prepared by coating nanosilver on the surface of LMPs through in situ chemical reduction. The critical stress at which rigid Ag shells rupture can be controlled by adjusting the Ag shell thickness so that LM cores with low moduli can release, achieving real‐time self‐repairing (within 200 ms) under external destruction. Furthermore, a flexible circuit utilizing Ag@LMPs is fabricated by screen printing, and exhibits outstanding stability and durability (R/R₀ < 1.65 after 10 000 bending cycles in a radius of 0.5 mm) because of the functional core–shell structure. The self‐repairable Ag@LMPs prepared in this study are a candidate filler for flexible circuit design through multiple processing methods.     

Novel Core–Shell FeOF/Ni(OH)2 Hierarchical Nanostructure for All‐Solid‐State Flexible Supercapacitors with Enhanced Performance

Well‐controlled core–shell hierarchical nanostructures based on oxyfluoride and hydroxide are for the first time rationally designed and synthesized via a simple solvothermal and chemical precipitation route, in which FeOF nanorod acts as core and porous Ni(OH)₂ nanosheets as shell. When evaluated as electrodes for supercapacitors, a high specific capacitance of 1452 F g^?1 can be obtained at a current density of 1 A g^?1. Even as the current density increases to 10 A g^?1, the core–shell hybrid still reserves a noticeable capacitance of 1060 F g^?1, showing an excellent rate capacity. Furthermore, all‐solid‐state flexible asymmetric supercapacitor based on the FeOF/Ni(OH)₂ hybrid as a positive electrode and activated carbon as a negative electrode shows high power density, high energy density, and long cycling lifespan. The excellent electrochemical performance of the FeOF/Ni(OH)₂ core–shell hybrid is ascribed to the unique microstructure and synergistic effects. FeOF nanorod from FeF₃ by partial substitution of fluorine with oxygen behaves as a low intrinsic resistance, thus facilitating charge transfer processes. While the hierarchical Ni(OH)₂ nanosheets with large surface area provide enough active sites for redox chemical reactions, leading to greatly enhanced electrochemical activity. The well‐controllable oxyfluoride/hydroxide hybrid is inspiring, opening up a new way to design new electrodes for next‐generation all‐solid‐state supercapacitors.     

Magnetic/Silica Nanocomposites as Dual‐Mode Contrast Agents for Combined Magnetic Resonance Imaging and Ultrasonography

A simple and efficient method for synthesizing a range of hybrid nanocomposites based on a core of silica nanospheres (160, 330, and 660 nm in diameter) covered by an outer shell of superparamagnetic nanoparticles, either iron oxide or heterodimeric FePt‐iron oxide nanocrystals, is presented. The magnetic and ultrasound characterization of the resulting nanocomposites shows that they have great potential as contrast agents for dual‐mode imaging purposes, combining magnetic resonance imaging (MRI) and ultrasonography (US).     

Yolk–Shell Structured Assembly of Bamboo‐Like Nitrogen‐Doped Carbon Nanotubes Embedded with Co Nanocrystals and Their Application as Cathode Material for Li–S Batteries

Despite their high theoretical specific capacity (1675 mA h g^?1), the practical application of Li–S batteries remains limited because the capacity rapidly degrades through severe dissolution of lithium polysulfide and the rate capability is low because of the low electronic conductivity of sulfur. This paper describes novel hierarchical yolk–shell microspheres comprising 1D bamboo‐like N‐doped carbon nanotubes (CNTs) encapsulating Co nanoparticles (Co@BNCNTs YS microspheres) as efficient cathode hosts for Li–S batteries. The microspheres are produced via a two‐step process that involves generation of the microsphere followed by N‐doped CNTs growth. The hierarchical yolk–shell structure enables efficient sulfur loading and mitigates the dissolution of lithium polysulfides, and metallic Co and N doping improves the chemical affinity of the microspheres with sulfur species. Accordingly, a Co@BNCNTs YS microsphere‐based cathode containing 64 wt% sulfur exhibits a high discharge capacity of 700.2 mA h g^?1 after 400 cycles at a current density of 1 C (based on the mass of sulfur); this corresponds to a good capacity retention of 76% and capacity fading rate of 0.06% per cycle with an excellent rate performance (752 mA h g^?1 at 2.0 C) when applied as cathode hosts for Li–S batteries.     

Design of Hierarchical NiCo@NiCo Layered Double Hydroxide Core–Shell Structured Nanotube Array for High‐Performance Flexible All‐Solid‐State Battery‐Type Supercapacitors

A novel hierarchical nanotube array (NTA) with a massive layered top and discretely separated nanotubes in a core–shell structure, that is, nickel–cobalt metallic core and nickel–cobalt layered double hydroxide shell (Ni?Co@Ni?Co LDH), is grown on carbon fiber cloth (CFC) by template‐assisted electrodeposition for high‐performance supercapacitor application. The synthesized Ni?Co@Ni?Co LDH NTAs/CFC shows high capacitance of 2200 F g^?1 at a current density of 5 A g^?1, while 98.8% of its initial capacitance is retained after 5000 cycles. When the current density is increased from 1 to 20 A g^?1, the capacitance loss is less than 20%, demonstrating excellent rate capability. A highly flexible all‐solid‐state battery‐type supercapacitor is successfully fabricated with Ni?Co LDH NTAs/CFC as the positive electrode and electrospun carbon fibers/CFC as the negative electrode, showing a maximum specific capacitance of 319 F g^?1, a high energy density of 100 W h kg^?1 at 1.5 kW kg^?1, and good cycling stability (98.6% after 3000 cycles). These fascinating electrochemical properties are resulted from the novel structure of electrode materials and synergistic contributions from the two electrodes, showing great potential for energy storage applications.     

Cobalt–Cobalt Phosphide Nanoparticles@Nitrogen‐Phosphorus Doped Carbon/Graphene Derived from Cobalt Ions Adsorbed Saccharomycete Yeasts as an Efficient,Stable, and Large‐Current‐Density Electrode for Hydrogen Evolution Reactions

Development of electrocatalysts for hydrogen evolution reaction (HER) with low overpotential and robust stability remains as one of the most serious challenges for energy conversion. Herein, a serviceable and highly active HER electrocatalyst with multilevel porous structure (Co‐Co₂P nanoparticles@N, P doped carbon/reduced graphene oxides (Co‐Co₂P@NPC/rGO)) is synthesized by Saccharomycete cells as template to adsorb metal ions and graphene nanosheets as separating agent to prevent aggregation, which is composed of Co‐Co₂P nanoparticles with size of ≈104.7 nm embedded into carbonized Saccharomycete cells. The Saccharomycete cells provide not only carbon source to produce carbon shells, but also phosphorus source to prepare metal phosphides. In order to realize the practicability and permanent stability, the binderless and 3D electrodes composed of obtained Co‐Co₂P@NPC/rGO powder are constructed, which possess a low overpotential of 61.5 mV (achieve 10 mA cm^?2) and the high current density with extraordinary catalytic stability (1000 mA cm^?2 for 20 h) in 0.5 m H₂SO₄. The preparation process is appropriate for synthesizing various metal or metal phosphide@carbon electrocatalysts. This work may provide a biological template method for rational design and fabrication of various metals or metal compounds@carbon 3D electrodes with promising applications in energy conversion and storage.     

Creation of Redox‐Active PdSx Nanoparticles Inside the Defect Pores of MOF UiO‐66 with Unique Semihydrogenation Catalytic Properties

Semihydrogenation of alkynes to produce alkenes is very important in the industry; however, over‐hydrogenation heavily complicates the postprocesses, which are highly energy consuming and not environmentally friendly. One of the most efficient pathways to solve this challenging issue is to develop highly selective catalysts that could only hydrogenate alkynes and are inactive in hydrogenation of alkenes. This work presents herein an efficient catalyst, consisting of in situ created PdS_0.53 nanoparticles as the redox‐active sites inside the defect pores of metal–organic framework UiO‐66, which demonstrates very high alkene selectivity (up to 99.5%) in semihydrogenation of easily over‐hydrogenated terminal alkynes. In contrast to the traditional catalysts, strict control over the reaction time becomes the nonessential condition because the catalyst system is almost inactive in hydrogenation of alkenes. Therefore, this paradigm work provides a practically applicable pathway for the development of efficient catalysts with unique catalytic properties for selective semihydrogenation reactions.     

A Versatile Pt‐Based Core–Shell Nanoplatform as a Nanofactory for Enhanced Tumor Therapy

Hypoxia, one of the representative characteristics in solid tumors, not only reduces the effectiveness of multiple treatments, but also relates to the tumor invasion and metastasis. Here, a hybrid core–shell nanoplatform to produce adequate oxygen, supporting for more effective tumor treatment, is developed. Composed of polydopamine cores, platinum nanoparticle interlayers, and zirconium‐porphyrin (PCN) shells, the hybrid core–shell nanoplatform works like a nanofactory, providing necessary products at different time and space. Platinum nanoparticle interlayers can catalyze the endogenous H₂O₂ to O₂, which plays a dual rule in the enhanced tumor treatment. In the presence of light irradiation, O₂ can be converted into the lethal reactive oxygen species by the PCN shell. In the absence of light irradiation, O₂ ameliorates the hypoxic microenvironment, thereby reduces the invasion and metastasis of the tumor. Through a synergism of enhanced treatment and reduced metastasis, tumors could be treated more vigorously.     

Chirality on Hierarchical Self‐Assembly of Au@AuAg Yolk–Shell Nanorods into Core–Satellite Superstructures for Biosensing in Human Cells

Here, Au@AgAu yolk–shell nanorods (YSNRs) with tunable plasmonic circular dichroism (PCD) responses are synthesized, for the first time, using chiral d ‐ or l ‐penicillamine. The concentration of chiral molecules and the nanogap size play key roles in the PCD signal of the YSNRs. Importantly, the PCD response could be regulated by changing the aspect ratio of gold nanorods, and the largest anisotropy factor (g‐factor) is 0.009. Remarkably, the YSNRs are used as new chiroptical building blocks together with Au nanoparticles (NPs) to build YSNR@NP core–satellite (CS) assemblies, which display much stronger PCD intensity and an increased g‐factor of 0.021. The theoretical calculation data demonstrate that the significant PCD activity of nanoassemblies is originated from chiral structures and the intrinsic chirality of the building blocks. Noticeably, the developed CS superstructures with photothermal effects are utilized to quantitatively detect zinc ion in living cell lines. This study reports an emerging class of chiral inorganic nanostructures with important future applications, including enantioselective separation, asymmetric catalysis, and biomedical sensing.     

From Smart Denpols to Remote‐Controllable Actuators: Hierarchical Superstructures of Azobenzene‐Based Polynorbornenes

For the demonstration of remote‐controllable actuators, a dendronized polymer (denpol) is newly designed and successfully synthesized by ring‐opening metathesis polymerization of azobenzene‐based macromonomers. The incorporation of azobenzene mesogens into the denpols helps to construct finely tuned hierarchical superstructures with anisotropic physical properties and reversible photoisomerization. The polynorbornene backbones and azobenzene side chains in the uniaxially oriented films are aligned perpendicularly and parallel to the layer normal, respectively. Based on photoreversible actuation experiments combined with diffraction results, direct relationships between the chemical structures, hierarchical superstructures, and their corresponding photomechanical behaviors are proposed. Smart denpols possess great potential for practical applications in photoresponsive switches.     

Multifunctional Shell–Core Nanoparticles for Treatment of Multidrug Resistance Hepatocellular Carcinoma

Multidrug resistance (MDR) is the main obstruction against the chemotherapy for hepatocellular carcinoma. Herein, a biodegradable multifunctional tumor‐targeted core–shell structural nanocarrier (RGD peptide functionalized nanoparticles, RGD‐NPs) is reported for treating MDR hepatocellular carcinoma, which consists of three components: pH‐triggered calcium phosphate shell, long circulation phosphatidylserine‐polyethylene glycol (PS‐PEG) core, and an active targeting ligand RGD peptide. Drug‐resistance inhibitor (verapamil, VER) and chemotherapeutic agent (mitoxantrone, MIT) are separately encapsulated into the outer shell layer and inner core layer to obtain VER and MIT loaded RGD‐NPs (VM‐RGD‐NPs). Due to the shell–core structure, the VER and MIT can release sequentially, thus synergistically weakening the efflux effect to MIT by MDR cells. Also, the calcium phosphate can trigger lysosomal escaping through the varied pH value. Together with the optimized internalization pathway in MDR tumor cells, the increased intracellular effective chemotherapeutic drug concentration can be realized, thus achieving the improved curative effect. In this system, the PEG extends the circulation time in vivo. Also, the peptide RGD distinctly increases the affinity to MDR tumors with respect to nontargeted nanoparticles. As a consequence, VM‐RGD‐NPs exhibit a significant synergistic effect toward the MDR hepatocellular carcinoma, providing a promising therapeutic approach for MDR tumor.     

Rational Design of High‐Mobility Semicrystalline Conjugated Polymers with Tunable Charge Polarity: Beyond Benzobisthiadiazole‐Based Polymers

High‐mobility semiconducting polymers composed of arylene vinylene and dithiophene‐thiadiazolobenzotriazole (SN) units are developed by three powerful design strategies, namely, backbone engineering, heteroatom substitution, and side‐chain engineering. First, starting from the quaterthiophene‐SN copolymer, a vinylene spacer is inserted into the quaterthiophene unit for constructing highly‐planar backbones. Second, heteroatoms (O and N atoms) are incorporated into the thienylene vinylene moieties to tune the electronic properties and intermolecular interactions. Third, the alkyl side chains are optimized to tune the solubility and self‐assembly properties. As a consequence, a remarkable thin film transistor performance is obtained. The very high hole mobility of 3.22 cm² V^?1 s^?1 is achieved for the p‐type polymer, PSNVT‐DTC8, which is the highest value ever reported for the polymers based on the benzobisthiadiazole and its analogs. Moreover, heteroatom substitution efficiently varies the charge polarity of the polymers as in the case of the N atom substituted PSNVT_z‐DTC16 displaying n‐type dominant ambipolar properties with the electron mobility of 0.16 cm² V^?1 s^?1. Further studies using grazing‐incidence wide‐angle X‐ray scattering and atomic force microscopy have revealed the high crystallinities of the polymer thin films with strong π–π interactions and suitable polymer packing orientations.     

Poly(Acrylic Acid) Modification of Nd3+‐Sensitized Upconversion Nanophosphors for Highly Efficient UCL Imaging and pH‐Responsive Drug Delivery

In this work, a simple method is demonstrated for the synthesis of multifunctional core–shell nanoparticles NaYF₄:Yb,Er@NaYF₄:Yb@NaNdF₄:Yb@NaYF₄:Yb@PAA (labeled as Er@Y@Nd@Y@PAA or UCNP@PAA), which contain a highly effective 808‐nm‐to‐visible UCNP core and a thin shell of poly(acrylic acid) (PAA) to achieve upconversion bioimaging and pH‐sensitive anticancer chemotherapy simultaneously. The core–shell Nd³⁺‐sensitized UCNPs are optimized by varying the shell number, core size, and host lattices. The final optimized Er@Y@Nd@Y nanoparticle composition shows a significantly improved upconversion luminescence intensity, that is, 12.8 times higher than Er@Y@Nd nanoparticles. After coating the nanocomposites with a thin layer of PAA, the resulting UCNP@PAA nanocomposite perform well as a pH‐responsive nanocarrier and show clear advantages over UCNP@mSiO₂, which are evidenced by in vitro/in vivo experiments. Histological analysis also reveals that no pathological changes or inflammatory responses occur in the heart, lungs, kidneys, liver, and spleen. In summary, this study presents a major step forward towards a new therapeutic and diagnostic treatment of tumors by using 808‐nm excited UCNPs to replace the traditional 980‐nm excitation.