Uniform Mesopore Size Research Articles

A novel mesoporous carbon pocket with single atom Cr sites for high performance Lithium-Sulfur battery

Lithium-sulfur batteries (LSBs) are considered one of the most promising next-generation energy storage devices. However, their practical application is limited by the sluggish conversion kinetics and shuttle behavior of lithium polysulfides (LiPSs). In this work, we employ a facile salt template and micelle-mediated co-assembly strategy to synthesize atomic Cr dispersed mesoporous N-doped carbon pocket (denoted as Cr-mNC pocket). The designed Cr-mNC pocket exhibits uniform and ordered mesoporous caged morphology with a high surface area (843.5 m2/g), large pore volume (0.184 cm3 g−1), and uniform mesopore size (3.7 nm). The mesoporous structure offers a facilitated pump to promote electron/ion transportation while exposing more catalytic sites. These advantages enable the Cr-mNC pocket modified membrane to facilitate Li+ diffusion, enhance LiPSs adsorption, and accelerate electrochemical reaction kinetics for polysulfide conversion. Consequently, LSBs with Cr-mNC modified separator show a high sulfur utilization (1405 mAh g−1 at 0.2 C), a remarkable rate performance (776 mAh g−1 at 5 C), a low capacity decay rate of 0.047 % per cycle at 2 C over 1000 cycles, and even remain at 4.47 mAh cm−2 after 100 cycles with a high sulfur load of 5.0 mg cm−2.

A Novel Molten Salt Mediated Synthesis of Mesoporous Metal Oxides with High Crystallization.

The controlled synthesis of mesoporous metal oxides remains a great challenge because the uncontrolled assembly process and high-temperature crystallization can easily destroy the mesostructure. Herein, we develop a facile, versatile, low-cost, and controllable molten salt assisted assembly strategy to synthesize mesoporous metal oxides (e.g., CeO2, ZrO2, SnO2, Li2TiO3) with high surface area (115-155 m2/g) and uniform mesopore size (3.0 nm). We find this molten salt mediated assembly enables the desolvation of the precursors and forms bare metal ions, enhances their coordination interaction with the surfactant, and promotes their assembly into a mesostructure. Furthermore, the molten salt assisted crystallization process can lower the collision probability of the target metal atom, inhibit its further growth into large crystals, and achieve a well-maintained mesostructure with high crystallization. Furthermore, this method can be expanded to synthesize various structured mesoporous metal oxides, including hollow spheres, nanotubes, and nanosheets by introducing the carbon template. The obtained mesoporous CeO2 microspheres loaded with Cu species exhibit excellent antibacterial performance and superior catalytic activity for the hydrogenation of nitrophenol with high conversion and cycling stability.

The effect of the number of hydrophobic tails of cationic ammonium surfactants on mesoporous TiO2 synthesized

Mesoporous titanium dioxide (TiO2) is one of the most studied mesoporous materials considering its special character and various applications. In the present work, mesoporous TiO2 was synthesized by a sol–gel method employing different hydrophobic tails of ammonium cationic surfactants templates. The prepared samples were characterized by various techniques. The XRD profiles confirmed that all samples crystallized into the TiO2 anatase phase. The crystallite size of all samples was found to vary in the range of 8.60 nm to 13.61 nm. The transition temperature of the anatase phase was increased to several Celsius degrees since TiO2 was fabricated with a template assistant. The surface area of the mesoporous TiO2 was increased in the range of 93 m2.g−1 (CTAB) − 116.8 m2.g−1 (MTAB). These values were larger than the TiO2 synthesized without a template (72 m2.g−1). The total pore volume was also increased between 0.1704 cm3.g−1 (CTAB) and 0.300 cm3.g−1 (MTAB), while the TiO2 synthesized without a template was only 0.161 cm3.g−1. Using CTAB and DDAB yield a uniform mesopore size distribution. MTAB tends to produce non-uniform pore of the mesoporous system. The soft-templating method opens up new possibilities for synthesizing mesoporous metal oxides.

Development of Microdrip Enzyme Device Using Carbon-Coated Porous Silica Spheres

Carbon-coated porous silica spheres (C/PSSs) are particles with uniform particle and mesopore sizes, on which a thin layer of carbon is uniformly deposited on the surface by chemical vapor deposition. The continuous carbon deposit over the mesopore network allows the C/PSS to be electrically conductive and more chemically stable over its traditional counterparts, such as PSS, porous carbons, and carbon electrodes. As homogeneous particles, C/PSS can also be arranged uniformly on an electrode by screen printing to construct macroscopic networks that facilitate the diffusion of substances. Herein, C/PSS was synthesized and fabricated into a working electrode for a prototype glucose enzyme sensor to perform electrochemical measurements on a sample size of 20 μL. We selected the two enzymes, glucose dehydrogenase (GDH) and glucose oxidase (GOD), and water-soluble mediators, quinoline-5,8-dione (QD), to demonstrate the functionality of the sensor. The GDH sensor achieved a linear response up to 75 mM glucose concentration much higher than commercial sensor strips and the GOD sensor up to 25 mM. The results proved that the response current was mainly controlled by glucose diffusion. We succeeded in developing a sensor chip with C/PSS arranged on the surface with high efficiency by selecting a mediator that can smoothly transfer electrons to and from carbon, which enables various sensing applications. This work is the demonstration of the triple pore structure of the C/PSS electrode for enzyme electrode reactions.

Kinetics‐Controlled Synthesis of Ordered Mesoporous Carbon Single Crystals from Liquefied Wood

AbstractThe architectures of carbon materials prepared via soft‐templating method greatly depend on the assembly pattern of micelles. Herein, a kinetics‐controlled strategy is developed to fabricate ordered mesoporous carbon (OMC) single crystals from liquefied wood by using melamine to regulate the polymerization rate of carbon precursors, which further affects the assembly process. Due to the slow hydroxymethylation reaction of melamine with formaldehyde in acid, the addition of melamine can decelerate the reaction kinetics to produce no seed nuclei at the initial stage, which favors the composite micelles to orderly aggregate and further grow in a layer‐by‐layer pattern to form OMC single crystals after carbonization. The OMC single crystals with high specific surface areas (733 m2 g−1), uniform mesopore size (3.2 nm), and ordered Im3m mesostructure are ideal supports to couple with Ag nanoparticles to act as efficient catalysts, which exhibits remarkable catalytic performance for the reduction of 4‐nitrophenol.

Tailoring the impact of synthetic strategies on the catalytic upgrading of crude glycerol to produce bio-based aromatics in hierarchical HZSM-5

The catalytic upgrading of renewable biomass derived crude glycerol to generate bio-based aromatics is a promising alternative to petroleum route for the synthesis of valuable and versatile aromatics. The effects of synthetic strategies on the physicochemical property of hierarchical HZSM-5 as well as their corresponding catalytic upgrading performances of crude glycerol to bio-based aromatics were systematically investigated in this work. HZSM-5/0.3M NaOH catalyst exhibited smaller improvement in aromatic yields than microporous HZSM-5, which could be ascribed to the uncontrollable large intra-mesopore diameter and less increment in the amounts of acid sites during the introduction of mesoporosity via destructive alkali treatment. The soft templated HZSM-5/TPOAC catalyst produced more BTX and C9+ monocyclic aromatics, which could be attributed to its larger crystal sizes, higher external surfaces, luxuriant L acid amounts, uniform and small mesopore sizes. However, the hard templated HZSM-5/CNT-OH catalyst exhibited higher yields of polycyclic aromatic hydrocarbons and coke during the crude glycerol upgrading process, which could be assigned to its smaller crystal sizes, abundant B acid quantities, uniform and large mesopore diameters. The reusability of desilicated HZSM-5/0.3M NaOH was also deteriorated than the templated HZSM-5/CNT-OH and HZSM-5/TPOAC due to the inferior stability of incorporated mesoporosity via desilication. Finally, plausible reaction pathway involved catalytic upgrading of crude glycerol to produce aromatics was proposed in detail.

Homomesoporous Metal-Organic Framework for High-Performance Electrochromatographic Separation.

Metal-organic frameworks (MOFs) have exhibited tremendous potential in the area of separation science. However, most of the developed MOF-based stationary phases contained only microporous structures and suffer from limited separation performance. Herein, homomesoporous MOFs with excellent mass transfer capability and strong thermodynamic interactions are first explored as the novel stationary phase for high-performance capillary electrochromatographic separations. As a proof of concept, noninterpenetrated mesoMOF-1 with uniform mesopore sizes (22.5 × 26.1 Å) and good stability was facilely grown on the inner surface of capillaries and applied as a homomesoporous MOF coating-based stationary phase for high-efficiency electrochromatographic separation. Seven types of analytes with different molecular dimensions were all baseline separated on a mesoMOF-1 coated column with high theoretical plate numbers and excellent repeatability, exhibiting significantly improved separation selectivity and column efficiency in comparison to a microporous HKUST-1 coated column. The maximum column efficiencies of the mesoMOF-1 coated column for substituted benzenes and halobenzenes reached up to 1.4 × 105 plates/m, and its mass loadability was also much higher than that of the HKUST-1 coated column. In addition, based on the analysis of adsorption kinetics and chromatographic retention behaviors, the interaction and retention mechanisms of different molecular-weight analytes on mesoMOF-1 coated stationary phases were systematically explored and disclosed in detail. These results indicate that the homomesoporous MOF-based stationary phase can effectively balance the kinetic diffusion (mass transfer capability) and thermodynamic interactions (the strength of adsorption interaction), having great potential for high-performance chromatographic separation.

Interfacial Catalysis Enabled Acetone Sensors Based on Rationally Designed Mesoporous Metal Oxides with Erbium‐Doped WO3 Framework

AbstractThe emerging combination of Internet of Things requires the development of intelligent gas sensor, and semiconductor gas sensors based on metal oxides have been widely applied in industrial production, environmental monitoring, and food safety. Although versatile nanomaterials have been exploited as gas sensitive materials, restricted gas sensing performance including sensitivity, selectivity and stability, is still the fatal problem of practical applications. Herein, inspired by heteratomic doping engineering, unique rare earth erbium (Er)‐doped mesoporous tungsten oxide (Er/mWO3) has been synthesized via one‐step collaborative coassembly strategy, and Er ion‐doped mWO3 exhibited peculiarly hexagonal mesostructure (P63/mmc), tunable specific surface area (58.1–78.3 m2 g–1), uniform mesoporous size and highly crystallized framework with heteroatomic pore wall doping. The introduction of Er can significantly adjust the micro/nano structure and band characteristics, and 1.5 wt% Er‐doped mWO3 displays superior acetone sensing performance, including high response values (107 for 50 ppm), rapid response–recovery dynamics (9/56 s), prominent acetone selectivity, low concentration detection (125 ppb), anti‐humidity property and excellent long‐term stability. Such an excellent sensing performance is mainly attributed to unique interfaces catalytic sites induced by heteroatom interstitial doping. This finding opens a door for the design of smart gas sensors for environmental monitoring and industrial safety.

Recyclable nanopaper separators with uniform sub-20 nm nanopores for high-power and high-capacity zinc metal anodes

Despite the rising demand of low-cost and safe rechargeable batteries has triggered the intensive research on aqueous zinc ion batteries (AZBs), the impact of the separator on the performance of zinc metal anode is still largely neglected. Herein, a sustainable nanocellulose paper is proposed as an advanced AZB separator, featuring recyclability, lightweight, high mechanical strength, and high surface flatness as well as narrowly distributed sub-20 nm mesopores. In comparison with conventional separators, the effect of separator's pore structure (i.e., mesopore size and pore size distribution) on the reversibility of Zn deposition/stripping has been decoupled for the first time. It is found that such separator with uniform mesopore size distribution can render more homogenous Zn2+ flux over the entire electrode surface, eliminate the detrimental “tip effect” at the nanoscale level. Consequently, compact and uniform Zn deposits and exceptional cyclability are achieved at harsh test conditions (450 h at 10 mA cm−2 for 5 mAh cm−2 and 110 h under 30 mA cm−2 for 15 mAh cm−2). Moreover, the nanocellulose separator can be recycled from spent AZBs via a low-cost water-based approach, exhibiting sound electrochemical performance. This work provides a sustainable strategy and new insights to stabilizing Zn electrodes for high-performance AZBs merely by separator designing.

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.

Catalytic activity of hierarchical beta zeolites in the Prins cyclization of (−)-isopulegol with acetone

Several hierarchical beta zeolites prepared via hydrothermal treatment of a concentrated zeolite gel-precursor were investigated in Prins cyclisation between (–)-isopulegol and acetone acting as a reactant and a solvent for production of a chromenol compound exhibiting antiviral activity. The catalysts were characterized by SEM, TEM, nitrogen physisorption, ammonia TPD, adsorption-desorption of pyridine and 2,4,6-tri-tert-butylpyridine with FTIR spectroscopy. For the Prins cyclization performed at 30 °C, the highest yield of the desired product was obtained over a zeolite catalyst containing a developed mesoporosity with a uniform mesopore size and an optimum ratio of Brønsted to Lewis acid sites.

Recognizing adsorption of Cd(Ⅱ) by a novel core-shell mesoporous ion-imprinted polymer: Characterization, binding mechanism and practical application

A novel monodispersed Cd(II) ion-imprinted polymer (IIP) was synthesized inside core-shell mesoporous silica (C-SMS) particles to improve the diffusion kinetics of the polymer. The synthesized IIP@C-SMS was characterized and subsequently used in solid-phase extraction (SPE) for the selective adsorption of Cd(II) in aquatic samples. The results indicated that IIP had been successfully assembled inside the C-SMS particles with a high specific surface area (546.3 m2 g−1) and uniform mesoporous size (2.07 nm). The obtained IIP@C-SMS takes only 15 min to reach the adsorption equilibrium due to the highly developed mesoporous structure. IIP@C-SMS also presented a maximal adsorption capacity (201.9 μmol g−1) for Cd(II), which was much higher than that of NIP@C-SMS (80.3 μmol g−1). The relative selectivity coefficient of IIP@C-SMS for Cd(II)/M(II) (M = Cu(II), Pb(II), Cr(II), and Ni(II)) were 7.15, 8.70, 7.18, and 7.36, respectively, further confirming the satisfactory selectivity of IIP@C-SMS. The adsorption isotherms of IIP@C-SMS toward Cd(II) could be described by Langmuir model; whereas the adsorption kinetics could be fitted by the pseudo-second-order model, indicating chemisorption was the rate-limiting step. The FT-IR, ITC and XPS analysis further confirmed that the Cd(II)-induced cavities during the ion-imprinting process and the coordination between Cd(II) and –SH groups were the main adsorption mechanism. Furthermore, in real samples, IIP@C-SMS-SPE adsorbed approximately 93–104% of Cd(II). This work provides new insights for the design of novel macroporous sorbents for Cd(II).

Biomass-Derived Graphitic Carbon/Co3O4 Nanocomposites with Pseudocapacitance for Lithium Storage

The reuse of waste biomass resources has recently become one of the most popular themes in the sustainable development of human society. To this end, waste scallion root was used as a biotemplate and carbon source to synthesize graphitic carbon-doped mesoporous Co3O4 nanocomposites (Co3O4/C) through a simple cobalt salt impregnation, carbonization, and low-temperature oxidation method. The effect of different carbon contents on the nanostructure and electrochemical performance is investigated. The hierarchical microtubes with a ribs-shaped inner wall in the product oxidized at 320 °C (Co3O4/C-2) are formed by the cross-linking of uniform small Co3O4 nanoparticles and 39.9% biomass-derived carbon. The Co3O4/C-2 nanocomposite has a large specific surface area of 360.2 m2·g–1, uniform mesopore size of 2.35 nm, and abundant oxygen vacancy defects. Such a unique nanostructure can exhibit a good pseudocapacitance behavior during the charge/discharge process, thereby effectively enhancing the lithium storage performance. The Co3O4/C-2 nanocomposite exhibits a high capacity and good rate capability. Even at 1.0 A g–1, it can still retain a capacity of 620 mA h g–1 after 1500 cycles. The superior capacity retention and long-cycling stability can be assigned to the synergistic effect of the unique nanostructure of the Co3O4/C-2 material (a uniform mesopore and large specific surface area), appropriate graphitic carbon doping, and pseudocapacitance contribution. Therefore, the reuse strategy of the waste scallion root biomass resource conforms to the concept of sustainable development and also provides a useful reference for the synthesis of other nanostructured anode materials with excellent performance.

Biotemplate synthesis of mesoporous α-Fe2O3 hierarchical structure with assisted pseudocapacitive as an anode for long-life lithium ion batteries

The oriented biotemplate synthesis of nanostructured metal oxides as anode materials for lithium-ion batteries (LIBs) has recently attracted widespread attentions. Herein, mesoporous α-Fe2O3 hierarchical tubes (named as Fe-400) were successfully prepared by facile iron salt impregnation and air calcination at 400 °C using waste poplar branch as biotemplate. The hierarchical structure of Fe-400 is constructed from cross-linked small nanoparticles (~29 nm), which then results in large specific surface area (37.7 m2 g−1) and uniform mesoporous size distribution (12.2 nm). As anode material for LIBs, Fe-400 displays reversible capacity of 880.7 mA h g−1 after long-cycle of 800th at 1 A g−1, indicating that this material has high capacity retention and good long-cycle stability. The prominent electrochemical properties are mainly ascribed to the large specific surface area, unique homogeneous mesopores, and the assisted pseudocapacitive behaviors of Fe-400. In view of the low-cost, environment-friendly and easily large-scale synthesis of Fe-400 electrode material, the present biotemplate strategy can present useful reference for the synthesis of other transition metal oxide-based anode materials for LIBs.

Multistage Self-Assembly Strategy: Designed Synthesis of N-doped Mesoporous Carbon with High and Controllable Pyridine N Content for Ultrahigh Surface-Area-Normalized Capacitance

Nitrogen doping could improve the performance of carbon materials in electrocatalysis, CO2 adsorption, and energy storage. [1]However, the control of the doping type and the amount of nitrogen (N)-...

Amphiphilic Mesoporous Sandwich-Structured Catalysts for Selective Hydrogenation of 4-Nitrostyrene in Water.

Selective catalytic hydrogenation of substituted nitro compounds (NCs) of hydrophobic nature in aqueous solution using transition-metal-based catalysts is highly desirable yet fairly challenging. Herein, we propose the idea of amphiphilic mesoporous catalysts for selective hydrogenation of hydrophobic NCs in aqueous solution. The amphiphilic catalyst Co@Co-N-C@SBA-15 with a sandwich-like structure is constructed by a one-step solvent-free melting coating method. The catalyst has an external hydrophilic silica support that facilitates catalyst dispersion in water. It has unique Co-N-C catalytic layers uniformly coated in the inner mesopore surfaces of the silica support, which enhance the selective adsorption and activation of hydrophobic NCs. It has a high surface area (448.2 m2/g) and a uniform mesopore size (∼7.0 nm) for fast mass transportation. It possesses ultrafine metallic Co nanoparticles uniformly anchored within the N-doped carbon (N-C) layers for easy magnetic separation. These features make the catalyst excellent for the selective hydrogenation of 4-nitrostyrene to form 4-aminostyrene, with a high conversion of 98.0% in 1.0 h, a superior selectivity of 98.8%, and a good stability under mild conditions. A comprehensive study confirms the excellence of the amphiphilic mesoporous catalysts compared with other control catalysts. The Co-N sites are the intrinsic active sites. They can selectively adsorb and activate the nitro groups other than the vinyl groups, leading to superior selectivity. Water as the solvent results in the best performance compared with typical organic solvents probably because of an enhanced water-mediated hydrogen spillover and transfer.

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.

Sp2-Hybridized Carbon-Containing Block Copolymer Templated Synthesis of Mesoporous Semiconducting Metal Oxides with Excellent Gas Sensing Property.

In recent years, rational design of ordered mesoporous metal oxides, especially metal oxide semiconductors with adjustable pore architecture and framework compositions, has aroused extensive research interest owing to their unique electronic structures, long-range ordered porous framework, uniform mesopore size, and high specific surface area. Research on mesoporous materials has been booming in the past 30 years, and many synthesis methods have been developed, such as templating methods based on amphiphilic copolymers as soft templates or mesoporous carbon/silica as hard templates, respectively. Soft-templating synthesis has been considered as one of the most efficient and flexible methods in designing ordered mesoporous materials through the controllable interfacial induced coassembly process. However, most commercial amphiphilic copolymers, such as poly(ethylene oxide)- b-poly(propylene oxide) based Pluronic-type ones, suffer the drawback of poor thermal stability, because they are too easy to be decomposed even in inert atmosphere. Therefore, they are difficult to support the structures of mesoporous metal oxides under high calcination temperatures (>400 °C). To solve this challenge, we designed new amphiphilic block copolymers with high content of sp2-hybridized carbon in the hydrophobic segments that were relatively stable and could be in situ converted into residual carbon to support the mesoporous structure, via living free radical polymerization. We developed a variety of novel synthesis methods based on sp2-hybridized carbon-containing block copolymer, such as ligand-assisted assembly and resol-assisted assembly strategies, achieving a controllable and versatile synthesis of mesoporous semiconducting metal oxides with excellent gas sensing performance. In this Account, we first outline the features of sp2-hybridized carbon-containing block copolymers synthesized via living free radical polymerization, particularly their pyrolysis behavior in converting into residual carbon. Combining the solvent evaporation induced coassembly and the carbon-supported crystallization strategies, we realized the rational design of various ordered mesoporous semiconducting metal oxides (e.g., WO3, SnO2, Co3O4, In2O3, TiO2, ZnO) and the regulation of their architectural features. To overcome the fast hydrolysis rate of metal precursors and weak interaction between block copolymers and metal precursors, we developed efficient ligand-assisted (e.g., acetylacetone and acetic acid) coassembly and resol-assisted coassembly methods to retard hydrolysis behavior and enhance the interaction via hydrogen bonds, covalent bonds, electrostatic interactions, etc. We also highlight the applications of these ordered mesoporous semiconducting metal oxides of both n-type and p-type in gas sensing fields, and they show tremendous sensing performance due to their abundant active sites on electron depletion layer and rapid gas diffusion via accessible pore channels. Finally, on the basis of the classic surface-electron depletion layer model, we elucidated in depth the surface catalytic reactions between the target gas molecules and the activated species (e.g., the adsorbed oxygen species) in the surface of mesoporous metal oxides during sensing process. These newly developed soft-templating synthesis methods that rely on sp2-hybridized carbon-containing block copolymers will open a new avenue for the design and application of ordered mesoporous semiconducting metal oxides in various fields.

Large-scale synthesis of NiS@N and S co-doped carbon mesoporous tubule as high performance anode for lithium-ion battery

The simple and large-scale synthesis of metal sulfides@heteroatom-doped carbon tubules with high lithium storage performance is seldom reported. In this work, mesoporous NiS@N and S co-doped carbon (NiS@NSC) tubules were firstly prepared by nickel salt impregnation and subsequently calcination using absorbent cotton as template. The crystalline NiS nanoparticles with an average particle size of about 90 nm are uniformly embedded in the mesoporous tubular N and S co-doped carbon skeleton. The BET specific surface area is 200.8 m2 g−1 and the uniform narrow mesopore size distributes centered at 2.32 nm. As anode for lithium-ion batteries, it displays good cycling stability and rate capability, which retains a reversible capacity of 715.9 mA h g−1 after 200 cycles at 0.1 A g−1, and even at a high current density of 5 A g−1 the specific discharge capacity can retain 411.1 mA h g−1, which is higher than for most of the reported NiS@C composites. The good electrochemical performances are mainly attributed to the inherent characteristics of NiS@NSC hollow tubules, involving uniform mesopores, large specific surface area and highly conductive N and S co-doped carbon skeleton.

Fabrication of hydrophilic multilayer magnetic probe for salivary glycopeptidome analysis

Variations in salivary components are closely associated with the predisposition and state of disease, the abnormal changes of salivary glycopeptidome are usually discovered as perilous singals of serious disease. Therefore, the monitoring and analyzing of salivary glycopeptidome are of even more overriding importance. In this work, a low-cost layer-by-layer assembly strategy was adopted to fabricate a hydrophilic multilayer magnetic probe (dubbed Mag-m-G6P) for salivary glycopeptidome analysis. The successful construction of multilayer structure not only guaranteed the good dispersal of probe by protecting magnetic core from itself aggregation tendency, but also endowed the probe with multiple advantages including the good hydrophilicity, uniform mesopore size and strong magnetic responsiveness, etc. As expected, with the optimized experimental conditions, the multifunctional probe showed high enrichemnt sensitivity, unbiased enrichment ability, excellent size-exclusion ability and reusability and so on in the process of standard sample analysis. At last, the Mag-m-G6P was successfully applied to salivary glycopeptidome analysis on further combination with LC–MS/MS analysis, a total of 53 endogenous glycopeptides were identified from human saliva.