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Anode materials for Li-ion batteries have attracted significant research interest owing to the growing demand for efficient and cost-effective energy storage systems. Among the various anode materials being studied, silicon-based anodes have garnered considerable attention as a result of their potential to overcome many of the limitations associated with graphite anodes. However, silicon-based anodes undergo high volumetric expansion during cycling, which results in anode failure. In contrast, silicon-oxide-based (SiOx) materials exhibit limited volumetric expansion, making them viable candidates as anode materials in lithium-ion batteries. Despite this, there remain several challenges associated with SiOxanodes, including volumetric expansion (160–200%), poor capacity retention, and low initial coulombic efficiency. To address these issues, the incorporation of heteroatoms into SiOxanodes has been proposed as a promising strategy. In this review, we aim to provide an overview of the current state of research on SiOxanodes, including experiments and theoretical calculations, with a focus on the insertion of heteroatoms to improve the anode performance. In particular, we examine the effects of heteroatom incorporation on the anode conductivity, lithium diffusion, durability, and initial coulombic efficiency. In addition, we present a design strategy for the insertion of heteroatoms into the SiOxanodes. This review aims to provide a comprehensive understanding of the role of heteroatoms in SiOxanodes and highlight the potential for further research in this area.

[Display omitted] This study investigated the catalytic activity of vanadium-manganese supported on USY-zeolite as a catalyst for low-temperature NO removal, and embedded the powder catalyst in PTFE filter of bag filter. The V 2 O 5 -MnO 2 /USY-zeolite catalyst was prepared using the co-impregnation method, and the V 2 O 5 /MnO 2 ratio was 0/10, 2.5/7.5, 5/5, 7.5/2.5, or 10/0. The catalytic activity test for NH 3 -SCR(selective catalytic reduction) of NO was performed at 150–230 °C. An enhanced NO conversion above 60% was exhibited in the low-temperature region below 230 °C, and the NO removal efficiency increased as the MnO 2 content increased. The NH 3 -TPD and NO-TPD(Temperature Programmed Desorption) analysis confirmed that the NH 3 adsorption of the catalyst more significantly influences the NO removal performance than the NO adsorption. As the MnO 2 content on the catalysts increased, the strength and amount of adsorbed NH 3 increased, resulting in enhanced NO conversion. The catalyst-embedded PTFE (polytetrafluoroethylene) fiber was prepared by extruding physically mixed PTFE and catalyst powder. Scanning electron microscopy/energy dispersive X-ray spectroscopy confirmed that the catalyst was well dispersed on the surface and inside the PTFE fiber. The NO removal performance of the catalyst included PTFE fiber increased as the amount of the catalysts added was increased. [ABSTRACT FROM AUTHOR]

Surface chemistry of electrodes plays a critical role in the fields of electrochemistry and electric-field-assisted separation. In this study, making ingenious use of the ordered mesoporous structure of silica materials and the electrochemical stability of ionic liquids (ILs) when integrated with polyvinylpyrrolidone (PVP), the PVP-modified IL-mesoporous silica/platinum wire (Pt/PVP@meso-SiO2@IL) was fabricated to increase hydroelectric stability and avoid the problem of electrode polarization. The effect of different amounts of mesoporous silica material used to modify the surface of the Pt electrode was systematically investigated. As a result, we successfully obtained a highly ordered mesoporous Pt/PVP@meso-SiO2material with smooth surface. Because pentyl triethylamine bis(trifluoromethylsulfonyl) imide exhibits a wide electrochemical window between −3 to 3 V, this IL was chosen to modify mesopores under vacuum. Even after repeatedly applying electric field on Pt/PVP@meso-SiO2@IL 100 times, this working electrode remained stable and showed high hydroelectric stability. After verifying the feasibility of this method, it was successfully applied in the electric-field-assisted separation of 2.0 and 3.0 μm polystyrene particles without any impediment from electrode polarization problems. This work provides a brand-new insight for resolving the problem of electrode polarization by developing a versatile tool for the electroseparation of micro-objects.

The increased interest in smart and portable electronic gadgets has led to the development of flexible and wearable energy storage systems. Herein, the oxygen vacancy-enriched Na-MnO2-xis synthesized using a simple, scalable, and inexpensive electrodeposition method. The oxygen vacancy enrichment effectively enhances the conductivity and reaction kinetics of the Na-MnO2electrode. The Na-MnO2-xfilm electrode reveals an excellent specific capacitance of 395 F g−1at the scan rate of 5 mV s−1with high capacitance retention of 85.9 % after 10,000 cycles at a current density of 5 A g−1. To verify the practicability, three asymmetric supercapacitors (ASCs) (Mn3O4//Ti3C2Tx, Na-MnO2//Ti3C2Tx, and Na-MnO2-x//Ti3C2Tx) are fabricated and their respective performances are contrasted. The Na-MnO2-x//Ti3C2TxASC reveals a maximum energy density of 25 Wh kg−1at the power density of 1000 W kg−1, along with excellent capacitance retention of 98.8 % after 10,000 cycles. In addition, to validate the suitability of Na-MnO2-xelectrode for flexible energy storage, the flexible Na-MnO2-x//Ti3C2TxASC is fabricated that operates in the potential window of 2 V in PVA: Na2SO4polymer gel electrolyte and delivers a high volumetric energy density of 510.3 mWh cm−3at a power density of 40,483 mW cm−3. Moreover, the electrocatalytic activity of Na-MnO2-xthin films reveals an overpotential of 439.7 and 381.2 mV to drive a current density of 10 mA cm−2corresponding to HER and OER, respectively. Therefore, the electrodeposited, oxygen vacancy-enriched Na-MnO2-xfilm electrode has great potential to be used for both flexible energy storage and electrocatalysis.

Asymmetric Hybrid supercapacitor (AHS) is distinguished by a combination of electrostatic and electrochemical storage mechanisms. High performance of AHS is based on MoO3(MO) hybridized with reduced graphene oxide (rGO). In the present study, a single step hydrothermal method was used to synthesise MO and MoO3-rGO (MOG) nanohybrid materials. MO and MOG samples were then used to prepare electrodes. These electrodes were subjected to CV, GCD, and EIS analyses with three- and two-electrode systems. Results showed that the MOG-2 composite achieved a higher specific capacity of 607.82 C g−1than bare MO at 96 C g−1at a sweep rate of 2 mVs−1in the three-electrode system. Thus, rGO can effectively enhance active sites for redox reactions. At current density of 1 A g−1, the MOG//rGO had the highest specific capacity of 188.40 C g−1. Based on GCD evaluation, the HSC coin cell device had a maximum energy density of 36.78 Whkg−1and a power density 2546.84 Wkg−1and the device retained 87.6 % capacity after 10,000 cycles.

Mesoporous MoO 2 material exhibited excellent catalytic performance, recyclability and water tolerance for the acetalization of glycerol. [Display omitted] • Ordered mesoporous MoO 2 exhibited excellent catalytic activity for acetalization of glycerol. • Mesoporous MoO 2 could be recycled without a significant loss of activity loss, and easily regenerated. • Partial hydrophobic treatment significantly improved the water tolerance during the acetalization reaction. Highly ordered mesoporous molybdenum dioxide (meso-MoO 2) was successfully synthesized by a nano-replication method using a mesoporous silica template with 3D cubic Ia 3 d mesostructure. Structural analyses using X-ray diffraction, N 2 sorption, and electron microscopy indicated that the meso-MoO 2 material exhibited high surface area (106 m2/g), large pore volume (0.66 cm3/g), and well-defined mesopores. Under the optimized reaction conditions, the meso-MoO 2 catalyst showed excellent catalytic performances for the acetalization of glycerol with acetone (95.8% of glycerol conversion, and 97.8% of solketal selectivity) at 20 °C, due to its high surface area with large number of acid sites. During recycling, the meso-MoO 2 catalyst exhibited a slight decrease in activity; and after a simple regeneration at 350 °C, the catalytic performances could be completely recovered. More importantly, a partial hydrophobic treatment of the meso-MoO 2 catalyst dramatically enhanced the water-tolerance during the catalytic reaction. [ABSTRACT FROM AUTHOR]

Iron oxide anode materials for rechargeable lithium-ion batteries have garnered extensive attention because of their inexpensiveness, safety, and high theoretical capacity. Nanostructured iron oxide anodes often undergo negative fading, that is, unconventional capacity increase, which results in a capacity increasing upon cycling. However, the detailed mechanism of negative fading still remains unclear, and there is no consensus on the provenance. Herein, we comprehensively investigate the negative fading of iron oxide anodes with a highly ordered mesoporous structure by utilizing advanced synchrotron-based analysis. Electrochemical and structural analyses identified that the negative fading originates from an optimization of the electrolyte-derived surface layer, and the thus formed layer significantly contributes to the structural stability of the nanostructured electrode materials, as well as their cycle stability. This work provides an insight into understanding the origin of negative fading and its influence on nanostructured anode materials.

[Display omitted] • Fresh prepared Pd/SiO 2 shows superior CH 4 oxidation activity than Pd/Al 2 O 3. • Pd/SiO 2 shows serious deactivation after hydrothermal aging. • Deactivated Pd/SiO 2 catalysts can completely regenerate by H 2 reduction treatment. The removal of CH 4 is critical to address environmental concerns for developing natural gas vehicles (NGVs), because CH 4 has a 20-fold-greater contribution to the greenhouse effect than CO 2. Alumina supported Pd catalysts are widely used for CH 4 oxidation due to their superior catalytic activity and durability compared to other CH 4 oxidation catalysts. However, the continuous deactivation of Pd-based catalysts during vehicle applications needs further development of active and durable catalysts. Here, we report that Pd/SiO 2 can be active and durable catalysts for CH 4 oxidation in practically relevant condition via a simple reductive regeneration. CH 4 oxidation light-off curves of freshly prepared Pd/SiO 2 (air, 550 °C) present higher activity than those of Pd/Al 2 O 3 , but severe deactivation was observed after hydrothermal aging (HTA, air with 10% H 2 O) at 850 °C. However, X-ray diffraction (XRD), scanning transmission electron microscopy (STEM) and volumetric CO adsorption suggest that Pd/SiO 2 has similar particle sizes as Pd/Al 2 O 3 even after HTA, indicating that Pd/PdO particle sintering is not the origin of the deactivation of Pd/SiO 2. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) shows that the CO was not adsorbed on Pd/SiO 2 after HTA, whereas it was adsorbed on Pd/Al 2 O 3 after HTA. These results demonstrate that the deactivation of Pd/SiO 2 originates mainly from the blockage of the Pd/PdO surface by the SiO 2 overlayer formed during HTA. The Pd/PdO surfaces are re-exposed by a simple H 2 treatment at 500 °C, resulting in CO adsorption on the Pd/PdO surface and regeneration for CH 4 oxidation activity, which suggests that the Pd/PdO surface was re-exposed by a reduction treatment. This work also demonstrates that SiO 2 -supported Pd catalysts can be a good candidate for active and durable CH 4 oxidation catalysts by using the proper regeneration protocols. [ABSTRACT FROM AUTHOR]

High-performance hybrid supercapacitors (HSCs) have been developed by combining two different electrode materials with wide potentials and long cycling stabilities. To develop high-performance HSCs, molybdenum vanadium oxide (MVO) was hybridized with graphene oxide (GO). The system of hydrothermal chemical pathways was used to synthesize the MVO/rGO (MVOG) nanohybrid material. The optimal MVOG achieves the highest specific capacity of 714.85 C/g compared to the bare MVO of 270.73 C/g at a sweep rate of 2 mV/s. The HSC was fabricated with two electrodes, namely, optimal MVOG and rGO as cathode and anode, respectively. The HSCs exhibit a maximum capacity of 185.06 C/g, with an operating potential of 1.5 V in 2 M KOH, with a maximum energy and power density of 38.55 Wh/kg and 2434.38 W/kg, respectively. The investigation conducted in this study reveals that the hybridization of MVO with GO enhances the physiochemical and electrochemical properties. The prepared MVOG electrode shows a 3-fold increase in supercapacitive efficiency compared to the MVO electrode. Different nanohybrids using ternary metal oxides with rGO can be developed by the same chemical route and hybridization method.

The growing energy demands of daily life necessitate innovative solutions. Green approaches, which are universally accepted, advocate the use of renewable energy sources in conversion and storage systems. Research in nanomaterials has continually advanced, with the structures and shapes of these materials diversifying for a broad spectrum of applications. Supercapacitor-based systems are emerging as leading alternatives in contemporary trends among the various energy storage devices. In particular, transition metal dichalcogenides (TMDCs) are surfacing as novel supercapacitive electrode materials, thanks to ongoing research efforts. This review focuses on the technological development, characteristics, and properties of various transition metal chalcogenides used for supercapacitors. Mainly, molybdenum chalcogenides have been observed to be an emerging member of the TMDCs family that recently gained considerable attention for supercapacitor applications. This study briefly describes different synthesis methods and their parameters for molybdenum chalcogenide nanomaterials. The electrochemical properties like electrochemical impedance spectroscopy (EIS), specific capacitance (SC), cycling stability, energy density, and the power density of molybdenum chalcogenide-based supercapacitors have been discussed thoroughly with appropriate literature support.

The purpose of this study is to analyze the publicness of medical services in public and private medical institutions, with a focus on treatment performance using National Health Insurance data. Data from the National Health Insurance Service were used to compare the publicness of medical services in public and private medical institutions. Beta regression analysis was conducted after adjusting for the relevant characteristics to identify the impact on the public treatment performance of medical institutions. The public case rate of public health institutions was higher than that of private medical institutions. According to the type of medical care institution, the public case rate was higher in general hospitals and tertiary hospitals than in hospitals. Recently, it has often highlighted that increasing emphasis of profitability in the evaluation of public health institutions is damaging the publicness of medical services. Even in this study, it can be evaluated that the public case rate of public health institutions is not higher than that of private medical institutions.

Graphical abstract Highlights • Ethylenediaminetetraacetic acid (EDTA) grafted KIT-6 and KCC-1 was prepared. • KIT-6-EDTA showed high adsorption capacities for Nd3+ ions in water. • Adsorption equilibrium, isotherm, and kinetics were investigated. • KIT-6-EDTA reused for 5 cycles without deterioration in adsorption capacities. Abstract Ethylenediaminetetraacetic acid (EDTA)-functionalized KIT-6 and KCC-1 mesoporous silicas were prepared via post-synthesis grafting and examined for their ability to promote the recovery of rare earth metal ions such as Nd3+ from an aqueous medium. The obtained adsorption isotherms were fitted to the Langmuir model, which gave a maximum adsorption of Nd3+ ions of 109.8 and 96.5 mg/g for KIT-6-EDTA and KCC-1-EDTA, respectively, at 25 °C and pH 6. The adsorption kinetic profile of KIT-6 was faster than KCC-1. KIT-6 was also proved to be more stable against desorption under acidic regeneration conditions. [ABSTRACT FROM AUTHOR]

It is widely accepted that solid electrolyte interphase (SEI) layer of carbonaceous material is formed by irreversible decomposition reaction of an electrolyte, and acts as a passivation layer to prevent further decomposition of the electrolyte, ensuring reliable operation of a Li-ion battery. On the other hand, recent studies have reported that some transition metal oxide anode materials undergo reversible decomposition of an organic electrolyte during cycling, which is completely different from carbonaceous anode materials. In this work, we revisit the electrochemical reaction of an electrolyte that produces SEI layer on the surface of carbonaceous anode materials using soft X-ray absorption spectroscopy. We discover that the reversible formation and decomposition of SEI layer are also able to occur on the carbonaceous materials in both Li- and Na-ion battery systems. These new findings on the unexpected behavior of SEI in the carbonaceous anode materials revealed by soft X-ray absorption spectroscopy would be highly helpful in more comprehensive understanding of the interfacial chemistry of carbonaceous anode materials in Li- and Na-ion batteries.

Biogas conversion to syngas by steam reforming was studied over metal-foam-coated Pd–Rh catalysts with variable CeZrO 2 –Al 2 O 3 support compositions. Catalysts with a higher CeZrO 2 /Al 2 O 3 ratio exhibited greater CH 4 and CO 2 conversions and higher H 2 /CH 4 yields, while displaying lower H 2 /CO ratios and reduced coke formation. Catalytic stability tests over 200 h showed CH 4 and CO 2 conversion rates of 93–97% and 0–5%, respectively. CeZrO 2 -modification of the catalyst leads to reduction in the BET area and metal dispersion. Sintering was observed in used catalysts; however there was no clear correlation between the extent of morphological deterioration and the CeZrO 2 /Al 2 O 3 ratio of the catalyst support. [ABSTRACT FROM AUTHOR]

Current lithium ion battery technology is tied in with conventional reaction mechanisms such as insertion, conversion, and alloying reactions even though most future applications like EVs demand much higher energy densities than current ones. Exploring the exceptional reaction mechanism and related electrode materials can be critical for pushing current battery technology to a next level. Here, we introduce an exceptional reaction with a Co(OH)2material which exhibits an initial charge capacity of 1112 mAh g–1, about twice its theoretical value based on known conventional conversion reaction, and retains its first cycle capacity after 30 cycles. The combined results of synchrotron X-ray diffraction and X-ray absorption spectroscopy indicate that nanosized Co metal particles and LiOH are generated by conversion reaction at high voltages, and CoxHy, Li2O, and LiH are subsequently formed by hydride reaction between Co metal, LiOH, and other lithium species at low voltages, resulting in a anomalously high capacity beyond the theoretical capacity of Co(OH)2. This is further corroborated by AIMD simulations, localized STEM, and XPS. These findings will provide not only further understanding of exceptional lithium storage of recent nanostructured materials but also valuable guidance to develop advanced electrode materials with high energy density for next-generation batteries.

Highly ordered mesoporous CdxZn1–xS materials were obtained via a simple nanoreplication method using a mesoporous silica template with a 3-D bicontinuous cubic Ia3d mesostructure. Combined analyses using X-ray diffraction, N2sorption, electron microscopy, and diffuse reflectance UV–visible spectroscopy revealed that the ordered mesoporous ternary compound semiconductor materials exhibited well-developed crystalline frameworks, high surface areas of 80–120 m2g–1, uniform mesopore sizes of about 20 nm, ordered arrangement of mesopores, and outstanding visible light absorption properties. Photocatalytic activities were investigated by degradation of methylene blue and rhodamine B under visible light over the mesoporous CdxZn1–xS materials. Due to the high surface area and outstanding light absorption properties, the ordered mesoporous CdxZn1–xS exhibited excellent photocatalytic performances for the degradation of methylene blue and rhodamine B. This study indicates a potential application of the mesoporous compound semiconductors in the efficient visible-light-driven photolysis of organics that may cause environmental pollution.

•Catalytic pyrolysis of wood-plastic composite was investigated.•Low-cost catalysts provided the catalytic effect on aromatics formation.•Natural zeolite decreased the decomposition temperature of plastics.•Natural zeolite produced the large amount aromatic hydrocarbons.

Active and nonprecious-metal bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are vital components of clean energy conversion devices such as regenerative fuel cells and rechargeable metal–air batteries. Porous manganese oxides (MnOx) are promising electrocatalyst candidates because of their high surface area and the abundance of Mn. MnOxcatalysts exhibit various oxidation states and crystal structures, which critically affect their electrocatalytic activity. These effects remain elusive mainly because the synthesis of oxidation-state-controlled porous MnOxwith similar structural properties is challenging. In this work, four different mesoporous manganese oxides (m-MnOx) were synthesized and used as model catalysts to investigate the effects of local structures and Mn valence states on the activity toward oxygen electrocatalysis. The following activity trends were observed: m-Mn2O3> m-MnO2> m-MnO > m-Mn3O4for the ORR and m-MnO2> m-Mn2O3> m-MnO ≈ m-Mn3O4for the OER. These activity trends suggest that high-valent Mn species (Mn(III) and Mn(IV)) with disordered atomic arrangements induced by nanostructuring significantly influence electrocatalysis. In situ X-ray absorption spectroscopy was used to analyze the changes in the oxidation states under the ORR and OER conditions, which showed the surface phase transformation and generation of active species during electrocatalysis.

Solution-processed silver nanowire (AgNW) films have attracted attention as transparent and conductive electrodes for flexible optoelectronic devices and touch screens, to replace sputtered indium–tin-oxide (ITO) films. However, the mechanical flexibility, environmental durability, and the optical (such as transparency and a haze) and electrical properties of the AgNW films should be improved for their practical application. In this work, high-performance and roll-to-roll processed AgNW-based hybrid electrodes comprising poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and/or ITO are introduced. The optical and electrical properties of the AgNW films combined with PEDOT:PSS, ITO, or both of them were systematically examined. Among the films, the AgNW–PEDOT:PSS–ITO hybrid film exhibits a high transmittance (88%) and a low sheet resistance (44 Ω sq–1) with a small haze (1.9%). Moreover, the hybrid films show excellent durability to a variety of environmental stresses. By virtues of the high performance and durability, it is believed that the AgNW–PEDOT:PSS–ITO hybrid electrodes are highly suitable for practical use.

To monitor dynamic volume changes of electrode materials during electrochemical lithium storage and removal process is of utmost importance for developing high performance lithium storage materials. We herein report an in operandoprobing of mesoscopic structural changes in ordered mesoporous electrode materials during cycling with synchrotron-based small angel X-ray scattering (SAXS) technique. In operandoSAXS studies combined with electrochemical and other physical characterizations straightforwardly show how porous electrode materials underwent volume changes during the whole process of charge and discharge, with respect to their own reaction mechanism with lithium. This comprehensive information on the pore dynamics as well as volume changes of the electrode materials will not only be critical in further understanding of lithium ion storage reaction mechanism of materials, but also enable the innovative design of high performance nanostructured materials for next generation batteries.

In this study, the SiO polymer coating film was prepared the containing tetraethyl orthosilane (TEOS) solution by the sol-gel method on soda lime glass. After then, the plasma polymer coating was deposited on SiO polymer coated glass by plasma enhanced chemical vapor deposition (PECVD) method at room temperature during 15 seconds. The thiophene monomer was used as organic precursor. It was heat up to 60 oC and bubbled with hydrogen gas which flow rate was 50 sccm. Plasma was ignited by radio frequency (RF, 13.56 MHz) and its power was 10 W. SiO polymer and plasma polymer coated SiO polymer films were investigated by Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis.), water contact angle, the adhesion test, and the pencil hardness test. The IR spectra shows evidence of very thin organic plasma polymer, which could not be measured by SEM cross image. The SEM images show that the morphology of each film was not changed by plasma polymer coating. Low water contact angles showed with both coating. Moreover surface hardness was increased by plasma polymer coating.

Abstract: The capability for the adsorption of Cu(II)-ion with mesoporous silica materials, such as MCM-41, SBA-15 and XPD-2412, after functionalizing with amine groups, such as aminopropyltriethoxysilane (APTES), N(β-aminoethyl) γ-aminopropylmethyl dimethoxysilane (AEAPMDMS) and N1-(3-(trimethoxysilyl)-propyl) diethylenetriamine (TMSPDETA), was investigated in this study. N2 adsorption, XRD and elemental analysis methods were performed to gain an understanding of the structure and surface properties of the mesoporous silica materials. Of the absorbent materials, MCM-41, functionalized with APTES, showed the best activity for the adsorption of Cu(II)-ion. Compared with the mesoporous silica materials functionalized with APTES, those functionalized with AEAPMDMS and/or TMSPDETA showed lower adsorption capabilities, which may have been due to the locations of the amine groups. Most of the amine-organic domains were suggested should exist near the opening of channels or external surfaces. Furthermore, the rate of adsorption of Cu(II)-ions matched well with a pseudo-second-order kinetic model. [Copyright &y& Elsevier]

Hybrid light sensitizer: The exfoliated, layered, double hydroxide nanosheets induced a strong photochromic function in the anthraquinone sulfonate anions that were chemically immobilized on the nanosheets. This hybrid nanosheet was applied to the dye‐sensitized solar cell as a new light sensitizer that was self‐organized on TiO2spheres, resulting in a higher solar‐to‐electric conversion efficiency than the single‐dye cell, owing to the intense photochromic function of the hybrid nanosheets.

Carbon nanotube (CNT) and mesoporous TiO2composite (CNT/meso-TiO2) was synthesized by a nanocasting method using CNT-implanted mesoporous silica material as the template. The CNT was successfully incorporated within a mesoporous TiO2particle, and the CNT/meso-TiO2composite obtained exhibits a high surface area and well-established mesoporosity. Moreover, the composite material exhibits much lower electric resistance than those of mesoporous TiO2only and physical mixture of CNT and mesoporous TiO2, which probably due to the large interface area and strong junction between the implanted CNT and TiO2framework in the composite.

Highly ordered mesoporous iron oxide (α-Fe2O3)material has been successfully obtained from mesoporous silica template, KIT-6 (3-D Cubic Ia3d symmetry), through nano-replication method. The mesoporous α-Fe2O3material thus obtained exhibits well-defined mesopores (2.7 nm in diameter), high surface area (148 m2/g), high pore volume (0.47 cm3/g) and crystalline frameworks. The morphology of the mesoporous α-Fe2O3material is very uniform in spherical shape of which the average particle size is about 100 nm in diameter.

The selective catalytic reduction of NOx with NH3 (NH3-SCR) was investigated over Pt catalysts supported on various supports such as alumina, ZSM-5, SBA-15, and Al-SBA-15 with different amounts of alumina. Among them, Pt catalysts supported on Al-SBA-15 showed the higher NOx conversion at low temperatures than those of others. These also showed high NOx conversions over a wide reaction temperature. As the Si/Al ratio in Al-SBA-15 decreased, the NH3-SCR activity increased. This was closely related to the amount of strongly-adsorbed NH3.

In this study, we modified the surface of nanoporous carbons with carboxymethylated polyethyleneimine (CM-PEI) of a high charge density in order to increase the Pt loading on the nanoporous carbons in an aqueous solution. We carried out equilibrium adsorption tests of Pt(IV) on the pure nanoporous carbon and the CM-PEI-coated carbons and evaluated the adsorption isotherm on the CM-PEI-coated carbon using various isotherm models. It was found that the adsorption of Pt(IV) onto the CM-PEI-coated carbons obeys the Langmuir isotherm model.

Applicability of Al-MCM-48 as a catalyst for the linear low density polyethylene (LLDPE) degradation was investigated using a thermogravimetric analyzer as well as a batch reactor. The degradation products were analyzed by GC/MS, GC-TCD and GC-FID. The activation energy of LLDPE degradation was lowered by the addition of Al-MCM-48. The oil and gas yields were higher over Al-MCM-48 than those over Si-MCM-48. Al-MCM-48 generated mainly C7-C10 hydrocarbons, while Si-MCM-48 exhibited the relatively broader distribution of the oil products (C8-C14). Al-MCM-48 showed high catalytic stability for the LLDPE degradation.

To improve lipase activity and make the particulate carrier for practical application, lipase was conjugated to chitosan(Mwavg=80,000) by immine reaction. The lipase activity of conjugate was 93% of its initial activity at room temperature for 7 months, whereas the intact lipase activity decreased to 40%. And then, lipase-chitosan conjugate was intercalated within porous silica. The composite was characterized by X-ray diffraction, scanning electron microscopy, thermo gravimetric analysis. The Pore size was regulated in the range of 5~15nm. The maximum enzyme activity of lipase-chitosan conjugate needs the structure with 15nm pore of mesoporous silica. The resultant composite was found to have the free flowing property and keep up inner lipase activity.

We present the adsorption characteristics of uranyl ions on a new and innovative composite which was composed of a carboxymethylated polyethyleneimine (CM-PEI) and an activated carbon (F400) with a nanopore less than 2 nm in diameter. In this study, we examined the adsorption phenomena of uranyl ions on the CM-PEI/F400 composite and evaluated the adsorption data using various isotherm models. It was found that the adsorption of uranyl ions on the CM-PEI/F400 composite obeys the Langmuir isotherm model. In addition, it was observed that pH of solutions had great influence on the adsorption capacity of uranyl ions on the CM-PEI/F400 composite. Specially, the adsorption capacity of uranyl ions was linearly increased with an increase of pH at pH > 3.0.

A heterojunction structure between a cubic structured mesoporous titania thin film and polythiocyanogen inside the pores was prepared by electrodeposition technique. UV-Vis absorption and FT-IR spectra show that the electrodeposited material is polythiocyanogen and the SEM images show that polythiocyanogen is infiltrated into the pores of the mesoporous titania film. In addition, this heterojunction structure was fabricated into a photovoltaic cell and the cell performance was tested. The cell showed an overall efficiency of 0.03%.

The tribological performance of ordered mesoporous carbons (CMK-3) as lubricant additives is investigated at ambient temperature. The effects of CMK-3 on the frictional forces, wear amounts and cycles to scuffing are measured using a ball-on-disk tester. It was found that there was little difference in the frictional forces and wear amounts of the oils with and without CMK-3. However, the scuffing time of the oil with CMK-3 was much longer than that of the pure mineral oil in sliding tests. CMK-3 were very effective on maintaining the oil gap and protecting the surfaces in boundary lubricated sliding.

Highly ordered periodic mesoporous organosilica PMO materials with various mesostructures, including lamellar, bicontinuous cubic Ia3d, 2D hexagonal P6mm, 3D hexagonal P63mmc and cubic Pm3n, have been synthesized using Gemini surfactants with general formulas of CnH2n1NCH32CH2sN CH32CnH2n1Br2n 6–18 and s 3–12, Cn-s-n. The nature of the Gemini surfactant such as alkyl chain length n and spacer length s, and the synthetic conditions such as reaction temperatures and molar compositions are controlling parameters for desired mesostructures. The PMO materials, synthesized at room temperature from Cn-6-n, exhibit phase transition from lamellar to bicontinuous cubic Ia3d, 2D hexagonal, 3D hexagonal and cubic Pm3nas the chain length decreases, whereas only the lamellar and 2D hexagonal PMO materials with different lattice parameters depending on the chain length are obtained at high reaction temperature 373 K. The Cn-8-nand Cn-10-nsurfactants also yield 2D hexagonal PMO material in a very wide range of synthetic condition at 373 K. The PMO materials with various mesostructures thus obtained exhibit high BET surface areas in the range of 900–1500 m2g−1and total pore volumes of about 0.5–1.4 cm3g−1.

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Mesoporous molecular sieve MCM-41 with a Si/Al ratio of 35 was obtained by hydrothermal synthesis using a gel mixture with a molar composition of 6 SiO2:0.1 Al2O3:1 hexadecyltrimethylammonium chloride: 0.25 dodecyltrimethylammonium bromide: 0.25 tetrapropylammonium bromide:0.15 (NH4)2O:1.5 Na2O:300 H2O. The MCM-41 sample was calcined in O2 flow at 813 K and subsequently ion exchanged with Ca2+. A small Pt cluster has been supported on the MCM-41 sample following a procedure using ion exchange of Pt(NH3)42+. The Pt(NH3)42+ ion supported on MCM-41 has been activated in O2 flow at 593 K and subsequently reduced with Fh flow at 573 K, in the same way used for the preparation of a Pt cluster entrapped inside the supercage of zeolite NaY. The resulting Pt cluster supported on the MCM-41 shows hydrogen chemisorption oftotal two H atoms per Pt at 296 K (based on the total amount of Pt) and high catalytic activity for hydrogenolysis of ethane. The chemical shift in129Xe NMR spectroscopy of adsorbed xenon indicates that the Pt cluster is located inside the mesoporous molecular sieve.

Numerous studies have been conducted on a MoS2material owing to its high capacity and good rate capability as a promising substitute for commercial graphite materials in lithium-ion batteries. However, contrary to the continuous improvement in performance, the mechanism of the reversible lithium-ion storage in MoS2remains still unclear. Herein, we carried out an in-depth study about the lithium storage behavior of MoS2during the lithiation/delithiation process. The conversion reaction was verified by monitoring the reversible formation of the MoS2phase through the X-ray absorption and X-ray photoelectron spectroscopies. Moreover, reversible polysulfide reactions were demonstrated by investigating the sulfur redox reaction through the voltage profile comparison and X-ray photoelectron spectroscopy deconvolution. The results of systematic approach to the reaction mechanism present clear evidence that both the polysulfide reaction (S + 2Li++ 2e−↔ Li2S) and the conversion reaction (MoS2+ 4Li++ 4e−↔ Mo + 2Li2S) contribute to the initial obtained capacities. Furthermore, these reactions were confirmed to occur not only in the initial cycle but also during subsequent cycles. The findings help to understand the distinct reaction mechanism of MoS2and provide crucial guidelines for developing promising conversion-based anode materials as next-generation rechargeable batteries.

Highly ordered mesoporous α-Mn2O3with well-defined mesopores, high surface area, and high oxygen vacancy exhibits excellent catalytic activity toward H2O2decomposition at low temperature.

The silylation of SBA-15 enhances the reducibility of cobalt oxides on a SBA-15 supported cobalt catalyst, and consequently increases the catalytic activity for Fischer–Tropsch synthesis of hydrocarbons from syngas and selectivity for longer chain products.

Combining both nano-replication and nano-imprinting techniques using dual silica templates provides a simple way to synthesize ordered mesoporous carbons with bimodal pore size distributions (∼1.5 nm and ∼3.5 nm).