Tandem Chemistry with Janus Mesopores Accelerator for Efficient Aqueous Batteries.

A reliable solid electrolyte interphase (SEI) on the metallic Zn anode is imperative for stable Zn-based aqueous batteries. However, the incompatible Zn-ion reduction processes, scilicet simultaneous adsorption (capture) and desolvation (repulsion) of Zn2+(H2O)6, raise kinetics and stability challenges for the design of SEI. Here, we demonstrate a tandem chemistry strategy to decouple and accelerate the concurrent adsorption and desolvation processes of the Zn2+ cluster at the inner Helmholtz layer. An electrochemically assembled perforative mesopore SiO2 interphase with tandem hydrophilic -OH and hydrophobic -F groups serves as a Janus mesopores accelerator to boost a fast and stable Zn2+ reduction reaction. Combining in situ electrochemical digital holography, molecular dynamics simulations, and spectroscopic characterizations reveals that -OH groups capture Zn2+ clusters from the bulk electrolyte and then -F groups repulse coordinated H2O molecules in the solvation shell to achieve the tandem ion reduction process. The resultant symmetric batteries exhibit reversible cycles over 8000 and 2000 h under high current densities of 4 and 10 mA cm-2, respectively. The feasibility of the tandem chemistry is further evidenced in both Zn//VO2 and Zn//I2 batteries, and it might be universal to other aqueous metal-ion batteries.

Boosted Oxygen Kinetics of Hierarchically Mesoporous Mo2C/C for High-current-density Zn-air Battery.

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.

Implanting Colloidal Nanoparticles into Single-Crystalline Zeolites for Catalytic Dehydration.

The encapsulation of functional colloidal nanoparticles (100 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≤1.3×108 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 (14 emu/g) and robust acidity (~0.83 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 100 hours).

Reviving Zn0 Dendrites to Electroactive Zn2+ by Mesoporous MXene with Active Edge Sites.

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

Hierarchical Confinement Effect with Zincophilic and Spatial Traps Stabilized Zn-Based Aqueous Battery.

Zn-based aqueous batteries (ZABs) have been regarded as promising candidates for safe and large-scale energy storage in the "post-Li" era. However, kinetics and stability problems of Zn capture cannot be concomitantly regulated, especially at high rates and loadings. Herein, a hierarchical confinement strategy is proposed to design zincophilic and spatial traps through a host of porous Co-embedded carbon cages (denoted as CoCC). The zincophilic Co sites act as preferred nucleation sites with low nucleation barriers (within 0.5 mA h cm-2), and the carbon cage can further spatially confine Zn deposition (within 5.0 mA h cm-2). Theoretical simulations and in situ/ex situ structural observations reveal the hierarchical spatial confinement by the elaborated all-in-one network (within 12 mA h cm-2). Consequently, the elaborate strategy enables a dendrite-free behavior with excellent kinetics (low overpotential of ca. 65 mV at a high rate of 20 mA cm-2) and stable cycle life (over 800 cycles), pushing forward the next-generation high-performance ZABs.

Camouflaged Virus-Like-Nanocarrier with a Transformable Rough Surface for Boosting Drug Delivery.

Due to non-specific strong nano-bio interactions, it is difficult for nanocarriers with permanent rough surface to cross multiple biological barriers to realize efficient drug delivery. Herein, a camouflaged virus-like-nanocarrier with a transformable rough surface is reported, which is composed by an interior virus-like mesoporous SiO2 nanoparticle with a rough surface (vSiO2 ) and an exterior acid-responsive polymer. Under normal physiological pH condition, the spikes on vSiO2 are hidden by the polymer shell, and the non-specific strong nano-bio interactions are effectively inhibited. While in the acidic tumor microenvironment, the nanocarrier sheds the polymer camouflage to re-expose its rough surface. So, the retention ability and endocytosis efficiency of the nanocarrier are great improved. Owing to it's the dynamically variable rough surface, the rationally designed nanocarrier exhibits extended blood-circulation-time and enhanced tumor accumulation.

Enzyme-Based Mesoporous Nanomotors with Near-Infrared Optical Brakes.

As one of the most important parameters of the nanomotors' motion, precise speed control of enzyme-based nanomotors is highly desirable in many bioapplications. However, owing to the stable physiological environment, it is still very difficult to in situ manipulate the motion of the enzyme-based nanomotors. Herein, inspired by the brakes on vehicles, the near-infrared (NIR) "optical brakes" are introduced in the glucose-driven enzyme-based mesoporous nanomotors to realize remote speed regulation for the first time. The novel nanomotors are rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of the SiO2@Au core@shell nanospheres and the enzymes-modified periodic mesoporous organosilicas (PMOs). The nanomotor can be driven by the biofuel of glucose under the catalysis of enzymes (glucose oxidase/catalase) on the PMO domain. Meanwhile, the Au nanoshell at the SiO2@Au domain enables the generation of the local thermal gradient under the NIR light irradiation, driving the nanomotor by thermophoresis. Taking advantage of the unique Janus nanostructure, the directions of the driving force induced by enzyme catalysis and the thermophoretic force induced by NIR photothermal effect are opposite. Therefore, with the NIR optical speed regulators, the glucose-driven nanomotors can achieve remote speed manipulation from 3.46 to 6.49 µm/s (9.9-18.5 body-length/s) at the fixed glucose concentration, even after covering with a biological tissue. As a proof of concept, the cellar uptake of the such mesoporous nanomotors can be remotely regulated (57.5-109 µg/mg), which offers great potential for designing smart active drug delivery systems based on the mesoporous frameworks of this novel nanomotor.

Streamlined Mesoporous Silica Nanoparticles with Tunable Curvature from Interfacial Dynamic-Migration Strategy for Nanomotors.

Streamlined architectures with a low fluid-resistance coefficient have been receiving great attention in various fields. However, it is still a great challenge to synthesize streamlined architecture with tunable surface curvature at the nanoscale. Herein, we report a facile interfacial dynamic migration strategy for the synthesis of streamlined mesoporous nanotadpoles with varied architectures. These tadpole-like nanoparticles possess a big streamlined head and a slender tail, which exhibit large inner cavities (75-170 nm), high surface areas (424-488 m2 g-1), and uniform mesopore sizes (2.4-3.2 nm). The head curvature of the streamlined mesoporous nanoparticles can be well-tuned from ∼2.96 × 10-2 to ∼5.56 × 10-2 nm-1, and the tail length can also be regulated from ∼30 to ∼650 nm. By selectively loading the Fe3O4 catalyst in the cavity of the streamlined silica nanotadpoles, the H2O2-driven mesoporous nanomotors were designed. The mesoporous nanomotors with optimized structural parameters exhibit outstanding directionality and a diffusion coefficient of 8.15 µm2 s-1.

Sequential Chemistry Toward Core-Shell Structured Metal Sulfides as Stable and Highly Efficient Visible-Light Photocatalysts.

A universal sequential synthesis strategy in aqueous solution is presented for highly uniform core-shell structured photocatalysts, which consist of a metal sulfide light absorber core and a metal sulfide co-catalyst shell. We show that the sequential chemistry can drive the formation of unique core-shell structures controlled by the constant of solubility product of metal sulfides. A variety of metal sulfide core-shell structures have been demonstrated, including CdS@CoSx , CdS@MnSx , CdS@NiSx , CdS@ZnSx , CuS@CdS, and more complexed CdS@ZnSx @CoSx . The obtained strawberry-like CdS@CoSx core-shell structures exhibit a high photocatalytic H2 production activity of 3.92 mmol h-1 and an impressive apparent quantum efficiency of 67.3 % at 420 nm, which is much better than that of pure CdS nanoballs (0.28 mmol h-1 ), CdS/CoSx composites (0.57 mmol h-1 ), and 5 %wt Pt-loaded CdS photocatalysts (1.84 mmol h-1 ).

Two-Dimensional Mesoporous Heterostructure Delivering Superior Pseudocapacitive Sodium Storage via Bottom-Up Monomicelle Assembly.

Two-dimensional (2D) heterostructures endowed with mesoporosities offer exciting opportunities in electrocatalysis, photocatalysis, energy storage, and conversion technologies due to their integrated functionalities, abundant active sites and shortened diffusion distance. However, layered mesostructures have not been combined due to the immense difficulties by conventional chemical, mechanical exfoliation or self-assembly approaches. Herein, we explore a bottom-up strategy, carried out under mild conditions, for the facile synthesis of monolayered mesoporous-titania-mesoporous-carbon vertical heterostructure with uniform mesopore size, which enables ultrahigh rate capability and cycling longevity for pseudocapacitive sodium-ion storage in nonaqueous electrolyte. Such a brand-new type of heterostructure consists of well-ordered monolayered mesoporous titania nanosheets and surrounding two mesoporous carbon monolayers assembled at both sides. Remarkably, the combination of interconnected large mesoporosity and heterointerface leads to highly promoted reversible pseudocapacitance (96.4% of total charge storage at a sweep rate of 1 mV s-1), and it enables the material to retain strong mechanical stability during the rapid sodiation and desodiation processes. This study reveals the importance of incorporating mesopores into heterointerface as a strategy for enhancing charge storage kinetics of electroactive materials.

Core-shell structured titanium dioxide nanomaterials for solar energy utilization.

Because of its unmatched resource potential, solar energy utilization currently is one of the hottest research areas. Much effort has been devoted to developing advanced materials for converting solar energy into electricity, solar fuels, active chemicals, or heat. Among them, TiO2 nanomaterials have attracted much attention due to their unique properties such as low cost, nontoxicity, good stability and excellent optical and electrical properties. Great progress has been made, but research opportunities are still present for creating new nanostructured TiO2 materials. Core-shell structured nanomaterials are of great interest as they provide a platform to integrate multiple components into a functional system, showing improved or new physical and chemical properties, which are unavailable from the isolated components. Consequently, significant effort is underway to design, fabricate and evaluate core-shell structured TiO2 nanomaterials for solar energy utilization to overcome the remaining challenges, for example, insufficient light absorption and low quantum efficiency. This review strives to provide a comprehensive overview of major advances in the synthesis of core-shell structured TiO2 nanomaterials for solar energy utilization. This review starts from the general protocols to construct core-shell structured TiO2 nanomaterials, and then discusses their applications in photocatalysis, water splitting, photocatalytic CO2 reduction, solar cells and photothermal conversion. Finally, we conclude with an outlook section to offer some insights on the future directions and prospects of core-shell structured TiO2 nanomaterials and solar energy conversion.

Melt Electrospinning Designs for Nanofiber Fabrication for Different Applications.

Nanofibers have been attracting growing attention owing to their outstanding physicochemical and structural properties as well as diverse and intriguing applications. Electrospinning has been known as a simple, flexible, and multipurpose technique for the fabrication of submicro scale fibers. Throughout the last two decades, numerous investigations have focused on the employment of electrospinning techniques to improve the characteristics of fabricated fibers. This review highlights the state of the art of melt electrospinning and clarifies the major categories based on multitemperature control, gas assist, laser melt, coaxial, and needleless designs. In addition, we represent the effect of melt electrospinning process parameters on the properties of produced fibers. Finally, this review summarizes the challenges and obstacles connected to the melt electrospinning technique.

Molecular Design Strategy for Ordered Mesoporous Stoichiometric Metal Oxide.

A molecular design strategy is used to construct ordered mesoporous Ti3+ -doped Li4 Ti5 O12 nanocrystal frameworks (OM-Ti3+ -Li4 Ti5 O12 ) by the stoichiometric cationic coordination assembly process. Ti4+ /Li+ -citrate chelate is designed as a new molecular precursor, in which the citrate can not only stoichiometrically coordinate Ti4+ with Li+ homogeneously at the atomic scale, but also interact strongly with the PEO segments in the Pluronic F127. These features make the co-assembly and crystallization process more controllable, thus benefiting for the formation of the ordered mesostructures. The resultant OM-Ti3+ -Li4 Ti5 O12 shows excellent rate (143 mAh g-1 at 30 C) and cycling performances (<0.005 % fading per cycle). This work could open a facile avenue to constructing stoichiometric ordered mesoporous oxides or minerals with highly crystalline frameworks.

Spatial Isolation of Carbon and Silica in a Single Janus Mesoporous Nanoparticle with Tunable Amphiphilicity.

Like surfactants with tunable hydrocarbon chain length, Janus nanoparticles also possess the ability to stabilize emulsions. The volume ratio between the hydrophilic and hydrophobic domains in a single Janus nanoparticle is very important for the stabilization of emulsions, which is still a great challenge. Herein, dual-mesoporous Fe3O4@mC&mSiO2 Janus nanoparticles with spatial isolation of hydrophobic carbon and hydrophilic silica at the single-particle level have successfully been synthesized for the first time by using a novel surface-charge-mediated selective encapsulation approach. The obtained dual-mesoporous Fe3O4@mC&mSiO2 Janus nanoparticles are made up of a pure one-dimensional mesoporous SiO2 nanorod with tunable length (50-400 nm), ∼100 nm wide and ∼2.7 nm mesopores and a closely connected mesoporous Fe3O4@mC magnetic nanosphere (∼150 nm diameter, ∼10 nm mesopores). As a magnetic "solid amphiphilic surfactant", the hydrophilic/hydrophobic ratio can be precisely adjusted by varying the volume ratio between silica and carbon domains, endowing the Janus nanoparticles surfactant-like emulsion stabilization ability and recyclability under a magnetic field. Owing to the total spatial separation of carbon and silica, the Janus nanoparticles with an optimized hydrophilic/hydrophobic ratio show spectacular emulsion stabilizing ability, which is crucial for improving the biphasic catalysis efficiency. By selectively anchoring catalytic active sites into different domains, the fabricated Janus nanoparticles show outstanding performances in biphasic reduction of 4-nitroanisole with 100% conversion efficiency and 700 h-1 high turnover frequency for biphasic cascade synthesis of cinnamic acid.

Uniform Ordered Two-Dimensional Mesoporous TiO2 Nanosheets from Hydrothermal-Induced Solvent-Confined Monomicelle Assembly.

Two-dimensional (2D) nanomaterials have been the focus of substantial research interest recently owing to their fascinating and excellent properties. However, 2D porous materials have remained quite rare due to the difficulty of creating pores in 2D nanostructures. Here, we have synthesized a novel type of single-layered 2D mesoporous TiO2 nanosheets with very uniform size and thickness as well as ordered mesostructure from an unprecedented hydrothermal-induced solvent-confined assembly approach. The F127/TiO2 spherical monomicelles are first formed and redispersed in ethanol and glycerol, followed by a hydrothermal treatment to assemble these subunits into single-layered 2D mesostructure owing to the confinement effect of highly adhered glycerol solvent. The obtained 2D mesoporous TiO2 nanosheets have a relative mean size at around 500 × 500 nm and can be randomly stacked into a bulk. The TiO2 nanosheets possess only one layer of ordered mesopores with a pore size of 4.0 nm, a very high surface area of 210 m2 g-1 and a uniform thickness of 5.5 nm. The thickness can be further manipulated from 5.5 to 27.6 nm via simply tuning precursor concentration or solvent ratio. Due to the well-defined 2D morphology and large mesoporosity as well as crystalline anatase mesopore walls, these uniform TiO2 nanosheets are capable of providing large accessible voids for sodium ion adsorption and intercalation as well as preventing volume expansion. As expected, these mesoporous TiO2 nanosheets have exhibited an excellent reversible capacity of 220 mAh g-1 at 100 mA g-1 as sodium-ion battery anodes, and they can retain at 199 mAh g-1 after numerous cycles at different current densities. The capacity is retained at 44 mAh g-1 even at a large current density of 10 A g-1 after 10 000 cycles, demonstrating a remarkable performance for energy storage.

New Insight into the Synthesis of Large-Pore Ordered Mesoporous Materials.

Ordered mesoporous materials (OMMs) have received increasing interest due to their uniform pore size, high surface area, various compositions and wide applications in energy conversion and storage, biomedicine and environmental remediation, etc. The soft templating synthesis using surfactants or amphiphilic block copolymers is the most efficient method to produce OMMs with tailorable pore structure and surface property. However, due to the limited choice of commercially available soft templates, the common OMMs usually show small pore size and amorphous (or semicrystalline) frameworks. Tailor-made amphiphilic block copolymers with controllable molecular weights and compositions have recently emerged as alternative soft templates for synthesis of new OMMs with many unique features including adjustable mesostructures and framework compositions, ultralarge pores, thick pore walls, high thermal stability and crystalline frameworks. In this Perspective, recent progresses and some new insights into the coassembly process about the synthesis of OMMs based on these tailor-made copolymers as templates are summarized, and typical newly developed synthesis methods and strategies are discussed in depth, including solvent evaporation induced aggregation, ligand-assisted coassembly, solvent evaporation induced micelle fusion-aggregation assembly, homopolymer assisted pore expanding and carbon-supported crystallization strategy. Then, the applications of the obtained large-pore OMMs in catalysis, sensor, energy conversion and storage, and biomedicine by loading large-size guest molecules (e.g., protein and RNA), precious metal nanoparticles and quantum dots, are discussed. At last, the outlook on the prospects and challenges of future research about the synthesis of large-pore OMMs by using tailor-made amphiphilic block copolymers are included.

Nanoengineering of Core-Shell Magnetic Mesoporous Microspheres with Tunable Surface Roughness.

Functional core-shell mesoporous microspheres with integrated functions, controlled structure, and surface properties and morphologies have received increasing attention due to their excellent physicochemical properties. Herein, core-shell magnetic mesoporous materials with cauliflower-like morphology and tunable surface roughness have been synthesized through a kinetics-controlled interface co-assembly and deposition of mesostructured nanocomposites on Fe3O4@RF microspheres (RF refers to resorcinol formaldehyde resin). The obtained microspheres, synthesized via this interface nanoengineering method, possess well-defined sandwich structure with a tunable rough morphology, uniform size (560-1000 nm), perpendicularly aligned mesopores (∼5.7 nm) in the outer shell, RF-protected magnetic responsive core, high surface area up to 382 m2/g, and large pore volume of 0.66 cm3/g. As a result of the unique surface features and magnetic properties, these microspheres exhibit excellent performance in stabilizing and oxygen-free manipulating aqueous solutions in petroleum ether by a magnetic field. They also exhibit superior cell uptake properties compared with traditional smooth core-shell magnetic mesoporous silica microspheres, opening up the possible applications in fast drug delivery in cancer therapy.

Plasmolysis-Inspired Nanoengineering of Functional Yolk-Shell Microspheres with Magnetic Core and Mesoporous Silica Shell.

Yolk-shell nanomaterials with a rattle-like structure have been considered ideal carriers and nanoreactors. Traditional methods to constructing yolk-shell nanostructures mainly rely on multistep sacrificial template strategy. In this study, a facile and effective plasmolysis-inspired nanoengineering strategy is developed to controllably fabricate yolk-shell magnetic mesoporous silica microspheres via the swelling-shrinkage of resorcinol-formaldehyde (RF) upon soaking in or removal of n-hexane. Using Fe3O4@RF microspheres as seeds, surfactant-silica mesostructured composite is deposited on the swelled seeds through the multicomponent interface coassembly, followed by solvent extraction to remove surfactant and simultaneously induce shrinkage of RF shell. The obtained yolk-shell microspheres (Fe3O4@RF@void@mSiO2) possess a high magnetization of 40.3 emu/g, high surface area (439 m2/g), radially aligned mesopores (5.4 nm) in the outer shell, tunable middle hollow space (472-638 nm in diameter), and a superparamagnetic core. This simple method allows a simultaneous encapsulation of Au nanoparticles into the hollow space during synthesis, and it leads to spherical Fe3O4@RF@void-Au@mSiO2 magnetic nanocatalysts, which show excellent catalysis efficiency for hydrogenation of 4-nitrophenol by NaBH4 with a high conversion rate (98%) and magnetic recycling stability.

Constructing Three-Dimensional Mesoporous Bouquet-Posy-like TiO2 Superstructures with Radially Oriented Mesochannels and Single-Crystal Walls.

Constructing three-dimensional (3-D) hierarchical mesostructures with unique morphology, pore orientation, single-crystal nature, and functionality remains a great challenge in materials science. Here, we report a confined microemulsion self-assembly approach to synthesize an unprecedented type of 3-D highly ordered mesoporous TiO2 superstructure (Level-1), which consists of 1 spherical core and 12 symmetric satellite hemispheres epitaxially growing out of the core vertices. A more complex and asymmetric TiO2 superstructure (Level-2) with 13 spherical cores and up to 44 symmetric satellite hemispheres can also be well manipulated by increasing the size or content of impregnated TiO2 precursor emulsion droplets. The obtained 3-D mesoporous TiO2 superstructures have well-defined bouquet-posy-like topologies, oriented hexagonal mesochannels, high accessible surface area (134-148 m2/g), large pore volume (0.48-0.51 cm3/g), and well single-crystalline anatase walls with dominant (001) active facets. More interestingly, all cylindrical mesopore channels are highly interconnected and radially distributed within the whole superstructures, and all TiO2 nanocrystal building blocks are oriented grown into a single-crystal anatase wall, making them ideal candidates for various applications ranging from catalysis to optoelectronics. As expected, the bouquet-posy-like mesoporous TiO2 superstructure supported catalysts show excellent catalytic activity (≥99.7%) and selectivity (≥96%) in cis-semihydrogenation of various alkynes, exceeding that of commercial TiO2 (P25) supported catalyst by a factor of 10. No decay in the activity was observed for 25 cycles, revealing a high stability of the mesoporous TiO2 superstructure supported catalyst.

Mesoporous Tungsten Oxides with Crystalline Framework for Highly Sensitive and Selective Detection of Foodborne Pathogens.

Foodborne pathogens like Listeria monocytogenes can cause various illnesses and pose a serious threat to public health. They produce species-specific microbial volatile organic compounds, i.e., the biomarkers, making it possible to indirectly measure microbial contamination in foodstuff. Herein, highly ordered mesoporous tungsten oxides with high surface areas and tunable pores have been synthesized and used as sensing materials to achieve an exceptionally sensitive and selective detection of trace Listeria monocytogenes. The mesoporous WO3-based chemiresistive sensors exhibit a rapid response, superior sensitivity, and highly selective detection of 3-hydroxy-2-butanone. The chemical mechanism study reveals that acetic acid is the main product generated by the surface catalytic reaction of the biomarker molecule over mesoporous WO3. Furthermore, by using the mesoporous WO3-based sensors, a rapid bacteria detection was achieved, with a high sensitivity, a linear relationship in a broad range, and a high specificity for Listeria monocytogenes. Such a good gas sensing performance foresees the great potential application of mesoporous WO3-based sensors for fast and effective detection of microbial contamination for the safety of food, water safety and public health.