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Optimized porous structure is a prerequisite for high performance Li‒O2 battery cathode. Macroporous-mesoporous carbon (MMC) is fabricated via a nano-replication method using mesoporous SiO2 (KIT-6) containing NiO as the template. By varying the amount of NiO in the KIT-6/NiO composite template, the amount of macropores inside MMC is easily controlled. The as-prepared MMC exhibits a highly porous structure with abundant ordered mesopores along with macropores that are larger than 200 nm in size. When the MMC is applied as the cathode material in a Li‒O2 battery, the cell exhibits greatly improved electrochemical performance in comparison to a cell using conventional ordered mesoporous carbon (OMC) without macropores. Systematic studies indicate that while mesopores in the OMC are clogged with Li2O2 formed during the early stage of discharge, the MMC sufficiently accommodates a large amount of Li2O2 in the pores. In addition, Li2O2 with poor crystallinity forms on the cathode containing MMC during subsequent discharge processes, which can be due to the accumulated side product and the limited size of pores. The formation of amorphous Li2O2 and the expedited mass transport through the interconnected meso- and macropores of MMC can attribute to the improved electrochemical performance of the MMC cathode material.

Lithiation–delithiation reactions in Li-ion batteries do exhibit a huge electrochemically driven volume change of the anode material between the lithium-free and lithiated-host states, which results in a gradually fading capacity. Minimizing this volume change of the electrode during cycling is essential to achieve stable electrochemical behavior and thus for innovating design of electrode materials for Li storage. Here, ordered mesoporous CoSn intermetallic anode materials with various Co/Sn atomic ratios are developed. A dual-buffer effect is discovered that accommodates the volume changes in the electrode material by not only repeatedly generating void nanospaces but also by incorporating electrochemically inactive elements. Novel insights into the nanostructural changes of electrode materials during the lithiation–delithiation process are obtained by in operando small angle X-ray scattering. The degrees of volume change and nanoscopic order are found to be highly dependent on the Co contents in the mesoporous CoSn intermetallic anode materials, being possible to achieve a durable nanostructured electrode upon prolonged cycling.

Despite intense studies into silicon anode materials, the large volume expansion of silicon remains a significant problem that reduces battery performance and shortens battery life. In this paper, a procedure to increase the cycle life of the silicon anode in full-cell configuration using a simple pre-lithiation method is proposed. By precisely controlling the thickness of the pre-deposited lithium through evaporation, the volume change of the silicon-containing anodes can be effectively reduced during discharge. A coin-cell fabricated with a high-capacity cathode and the pre-lithiated silicon–graphite anode shows improvements in cycling performance, as well as a higher discharge capacity. Electrochemical and microscopic analysis confirm that pre-lithiation successfully suppresses the volumetric changes. Thus, this work provides an effective method for the preparation of long-cycle-life Li-ion batteries containing silicon-based anodes.

Mesoporous transition metal dichalcogenides (TMDCs), composed of group VI metals (Mo and W) and chalcogens (S and Se), with 2-D layered crystalline frameworks and 3-D pore structures were successfully prepared via a melting-infiltration assisted nano-replication method using a mesoporous template KIT-6 with cubic Ia3d symmetry. Combined analysis using X-ray diffraction, N2 adsorption–desorption and electron microscopy indicated that the mesoporous TMDCs, thus obtained, exhibited high surface areas (87–105 m2 g−1), large pore volumes (0.21–0.25 cm3 g−1) and well-defined mesopores about 20 nm in diameters. The mesoporous TMDCs showed outstanding rate capabilities up to 2C as well as high reversible lithium storage capacities (MoS2 710 mA h g−1; MoSe2 744 mA h g−1; WS2 501 mA h g−1; WSe2 427 mA h g−1) without a remarkable fading of capacity.

Anode materials including graphite are known to be thermodynamically unstable toward organic solvents and salts and become covered by a passivating film (Solid electrolyte interphase, SEI) which retards the kinetics because of the high electronic resistivity. To achieve high performance in lithium ion batteries (LIBs), the SEIs are required to be mechanically stable during repeated cycling and possess highly ion-conductive. In this work, we have investigated an artificial pre-SEI on graphite electrode using a polymer binder containing lithium (i.e., a Li-copolymer of isobutylene and maleic anhydride, Li-PIMA) and its effect on the anode performances. During charging, the polymer binder with the functional group (–COOLi) acts as a SEI component, reducing the electrolyte decomposition and providing a stable passivating layer for the favorable penetration of lithium ions. Hence, by using the binder containing lithium, we have been able to obtain the first Coulombic efficiency of 84.2% (compared to 77.2% obtained using polyvinylidene fluoride as the binder) and a capacity retention of 99% after 100 cycles. The results of our study demonstrate that binder containing lithium we have used is a favorable candidate for the development of high-performance LIBs.

We report on a facile synthesis of the ordered mesoporous carbon (OMC) materials with systematically controlled microporosity and mesoporosity simultaneously through the nano-replication route using phosphoric acid as the acid catalyst and activation agent. The use of phosphoric acid affects the pore structures of OMC materials, such as the formation of numerous micropores by activation of the carbon framework and the enlargement of mesopores by spontaneous phase separation during the carbonization. The mesopore sizes, surface areas, total pore volumes, and micropore volumes of the OMC materials are highly dependent on the phosphoric acid content and can be systematically controlled in the range 3.7–7.5 nm, 1027–2782 m2 g–1, 1.12–3.53 cm3 g–1 and 0.34–0.95 cm3 g–1, respectively. OMC materials with systematically controlled pore structures were successfully synthesized using phosphoric acid as the carbonization catalyst and mesoporous silica materials with cubic Ia3d and 2-D hexagonal mesostructures as the templates. The phosphoric acid in the synthesis of ordered mesoporous carbon materials acts as the chemical activating agent for micropore generation of the carbon framework and pore-expanding agent for controlling of mesopore size, in addition to functioning as the acid catalyst. The present synthesis pathway is very useful for preparing OMC materials with tunable mesopore sizes and well-developed microporosities at the same time.

A thin, uniform carbon coating on Na2/3Fe1/2Mn1/2O2 (NFMO) using 2,3-dihydroxynaphthalene (DN) was prepared. Pristine and DN-coated samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). An amorphous nanolayer coating of carbon is obtained on the surface of the layered pristine material. The 0.2 wt% DN-coated NFMO exhibits excellent electrochemical performance. An initial discharge capacity of 178 mA h g−1 was obtained at a C-rate of 0.1 C; this capacity is 20% higher than bare NFMO. Capacity retention (77.8% at the 50th cycle) is also maintained comparable to bare NFMO (77.7% at the 50th cycle). The thin and uniform carbon layer leads to improvement of charging and discharging kinetics and protects against direct contact between cathode and electrolyte.

The desire to advanced lithium ion battery is growing with the expansion of electronic markets. Therefore, studies on making electrode materials with high energy density and long cycle life are actively conducted. Among those materials, silicon containing anode is one of the most important materials in making high energy density batteries because of the high theoretical capacity of silicon (~4200mAh/g). However, silicon containing anodes have the disadvantage of large initial irreversible capacity and continuous capacity loss due to large volume change of silicon. Because Li ions transferred from the cathode to the anode disappear without being reversibly used for charging and discharging, the capacity of the full cell becomes significantly smaller than expected. To solve this problem, pre-lithiation has been proposed as a powerful method which can be done through several methods including chemical and electrochemical pre-lithiation and pre-lithiation by direct-contact to lithium [1]. Pre-lithiation studies show that the Coulombic efficiency and discharge capacity dramatically increased. In this research, we propose a method to improve a cycle life of Li ion batteries with silicon containing anodes by applying pre-lithiation to suppress the volume change of silicon. We applied a direct pre-lithation method to increase the cycle life through depositing Li onto the anode; which has an impact on the manufacturing process and the accurate controlling of Li amount. When the coin cell was fabricated with a high capacity cathode and a pre-lithiated silicon containing anode, we were able to obtain not only high discharge capacity (~18%) but also enhanced cycle life characteristics (~30%). In order to investigate the cause of improved cycle life of the cell, three electrode electrochemical experiments were conducted, and then the charged/discharged state of the anode and the cathode are separately extracted in the full cell profile. Analysis of the extracted profiles confirms that the end-voltage of the anode with accurate amount of extra Li is lowered, which means that the silicon in the anode did not completely shrink after discharge. This result demonstrates that the pre-lithiation method is effective in reducing the volume change of the silicon during cycling. Electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM) also supported the above results. We would like to share this result through the presentation and hope that this work will provide an effective method to build a long cycle life Li ion battery with silicon-containing anodes. References [1] Holtstiege, florian, et al, Batteries, 4.1 (2018): 4

a b s t r a c t Highly ordered mesoporous metal oxides (meso-MOx) such as CeO2, Co3O4, Mn2O3, SnO2, and TiO2 were successfully synthesized by using nano-replication method, and Pd-loaded meso-MOx (Pd/meso- MOx) catalysts for CO oxidation were investigated. The catalysts were characterized by X-ray diffraction, N2 adsorption-desorption, electron microscopy, CO-temperature programmed desorption (CO-TPD), and H2-temperature programmed reduction (H2-TPR). All of the catalysts exhibited highly ordered mesostructure and a high surface area (>100 m 2 g

Highly ordered mesoporous cerium dioxide (meso-CeO2) was successfully synthesized using a facile solvent-free infiltration method from a mesoporous silica template, KIT-6. The meso-CeO2 material, thus obtained, exhibited well-defined mesostructure and high surface area (153 m2 g−1). The physicochemical properties of meso-CeO2 material and Pd-supported on meso-CeO2 (Pd/meso-CeO2) were characterized by electron microscopy, X-ray diffraction, N2 adsorption–desorption, and temperature-programmed experiments. The Pd/meso-CeO2 catalyst exhibited excellent catalytic activity for CO oxidation compared with those of other Pd/CeO2 catalysts which were prepared using nanocrystalline CeO2 and bulk-CeO2 as the supports. Moreover, a hydrogen pretreatment of the Pd/meso-CeO2 catalyst resulted in a remarkable increase of catalytic activity (T100 = 52 °C).

While increasing the multifunction of wearable devices such as smart watch, earphone, and glasses, the run-time of battery is getting more important to be a competitive product in the wearable market. In order to get more reliable and longer lasting battery, the concepts of 3D battery architecture have been suggested to improve energy density [1]. Several 3D microbattery architectures have been proposed to maximize the areal energy density and rate discharge capability by maintaining short ion-transport distances between cathode and anode [2]. However, the implementation of high areal capacity 3D electrode is difficult to fabricate due to the limitation of manufacturing processing [3]. Moreover, conventional fabrication technology of the thin film electrolyte cannot make good step coverage of the 3D conformal electrolyte. In this research, we propose technical approaches to fabricate a high energy density 3D battery structure with good step coverage of the 3D conformal electrolyte. First, we developed a high aspect ratio (=h/w, where h is height and w is width of cathode) 3D cathode which consists of only LiCoO2 with high electrode density without any binder and conductive additives. And then, two kinds of different solid electrolyte layers, LLZO and LiPON, were applied to the 3D conformal coating on the 3D cathode by sol-gel and CVD processing. The process of sol gel and CVD efficiently improved step coverage of 3D conformal electrolyte. Subsequently, Li-metal was evaporated to make a bed for striping and plating as anode. Finally, the 3D solid state battery was evaluated and analyzed for the feasibility study of a next generation battery. References [1] Jeffrey W. Long et al, Chemical review, 104 (2004) 4463-4492 [2] Stefania Ferrari et al, J. Power Sources, 286 (2015) 25-46 [3] Matthew Roberts et al, J. Mater. Chem, 21 (2011) 9876-90

Highly ordered mesoporous ruthenium dioxide (meso-RuO2) has been successfully synthesized by controlling the surface hydrophobicity of a mesoporous silica template (KIT-6) via a nano-replication method. The meso-RuO2 material, thus obtained, exhibits a well-defined mesostructure and high surface area (131 m2 g−1). The physicochemical properties of the meso-RuO2 material are characterized by electron microscopy, X-ray diffraction, N2 adsorption–desorption, temperature programmed techniques, and X-ray photoelectron spectroscopy. Pretreatment of the meso-RuO2 catalyst under different gas environments (O2, H2 and CO) strongly affects the catalytic activity towards CO oxidation. The meso-RuO2, pretreated by O2 flowing at 200 °C, exhibited excellent catalytic activity for CO oxidation, 100% CO conversion with long-term stability at room temperature, whereas the meso-RuO2 catalysts with pretreatment under other conditions are not very active at room temperature. It is found that the surface oxygen species generated on the meso-RuO2 during O2 pretreatment at 200 °C provide CO oxidation activity at room temperature.

Carbon nanotube (CNT) and mesoporous TiO 2 composite (CNT/meso- TiO 2) was synthesized by a nanocasting method using CNT-implanted mesoporous silica material as the template. The CNT was successfully incorporated within a mesoporous TiO 2 particle, and the CNT/meso- TiO 2 composite obtained exhibits a high surface area and well-established mesoporosity. Moreover, the composite material exhibits much lower electric resistance than those of mesoporous TiO 2 only and physical mixture of CNT and mesoporous TiO 2, which probably due to the large interface area and strong junction between the implanted CNT and TiO 2 framework in the composite.

Highly ordered mesoporous silver material was successfully synthesized from a mesoporous silica template (KIT-6) with 3-D channel structure using the nano-replication method. The effects of H 2 or O 2 pretreatments on the catalytic performance of the mesoporous silver were investigated using a temperature programmed CO oxidation technique in a fixed bed reactor. The mesoporous silver material that was pretreated with H 2 exhibited an excellent catalytic activity compared to the as-prepared and 0 2 -pretreated catalysts. Moreover, this present mesoporous silver material showed good catalytic stability. For the CO oxidation, the apparent activation energy of the H 2 -pretreated mesoporous silver catalyst was 61 ± 0.5 kJ mol -1 , which was also much lower than the as-prepared (132 ± 1.5 kJ mol -1 ) and O 2 -pretreated (124 ± 1.4 kJ mol -1 ) catalysts.

Mesoporous tin oxide (SnO 2 ) materials, exhibiting high surface areas, crystalline frameworks and various mesostructures, were successfully obtained by a facile solvent-free infiltration method from mesoporous silica templates. Various kinds of mesoporous silica materials, such as KIT-6 (bicontinuous 3-D cubic, Ia 3 d ), SBA-15 (2-D hexagonal, p 6 mm ), SBA-16 (3-D cubic with cage-like pores, Im 3 m ) and spherical mesoporous silica (disordered), were utilized as the hard templates. Tin precursor (SnCl 2 · 2H 2 O, m.p. 310–311 K) was infiltrated spontaneously within the mesopores of silica templates by melting the precursor at 353 K without using any solvent. The heat-treatment of SnCl 2 -infiltrated composite materials at 973 K under static air conditions and subsequent removal of silica templates by using HF result in the successful preparation of mesoporous SnO 2 materials. The mesostructures as well as the morphologies of mesoporous SnO 2 materials thus obtained were very similar with those of the mesoporous silica templates. The mesoporous SnO 2 materials exhibit high surface areas of 84–121 m 2 /g as well as high pore volumes in the range of 0.22–0.35 cm 3 /g. The present solvent-free infiltration method is believed to be a simple and facile way for the preparation of mesoporous materials via nano-replication from mesoporous silica templates.

E-mail: jimankim@skku.eduReceived July 15, 2008In the present work, Diels-Alder reaction of cyclopentadiene with ethylacrylate has been carried out by usingtwo types of mesoporous solid acid catalysts (Al-MCM-41, Al-MCM-48) with different pore structures. Thespecific topology of Al-MCM-48 (cubic Ia3d structure composed of two independent 3-D channel systems)exhibit higher activity and stereo-control than those of Al-MCM-41 (hexagonal packing of 1-D channels). Thephysical properties of Al-MCM-48 catalyst, such as high accessibility of reactants to the acid sites, spatialconfinement in the nanoscopic reactors, and 3-D channel network structure that are effective adsorption anddiffusion of reactants, play a crucial role in the present study.Key Words : Mesoporous catalyst, Al-MCM-48, Diels-Alder reaction, Cyclopentadiene, Ethylacrylate IntroductionDiels-Alder (DA) reactions have attracted much attentionas a powerful synthesis pathway and widely utilized insynthetic organic chemistry and in the chemical industry,due to the high degree of regio- and stereo-selectivity.

Highly ordered mesoporous iron oxide (α- Fe 2 O 3) material has been successfully obtained from mesoporous silica template, KIT-6 (3-D Cubic Ia3d symmetry), through nano-replication method. The mesoporous α- Fe 2 O 3 material 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- Fe 2 O 3 material is very uniform in spherical shape of which the average particle size is about 100 nm in diameter.

Developing electrode materials with high-energy densities is important for the development of lithium-ion batteries. Here, we demonstrate a mesoporous molybdenum dioxide material with abnormal lithium-storage sites, which exhibits a discharge capacity of 1,814 mAh g−1 for the first cycle, more than twice its theoretical value, and maintains its initial capacity after 50 cycles. Contrary to previous reports, we find that a mechanism for the high and reversible lithium-storage capacity of the mesoporous molybdenum dioxide electrode is not based on a conversion reaction. Insight into the electrochemical results, obtained by in situ X-ray absorption, scanning transmission electron microscopy analysis combined with electron energy loss spectroscopy and computational modelling indicates that the nanoscale pore engineering of this transition metal oxide enables an unexpected electrochemical mass storage reaction mechanism, and may provide a strategy for the design of cation storage materials for battery systems., Electrode materials with high energy density are important for the development of Li-ion batteries. Here, the authors report a molybdenum dioxide anode with abnormal lithium storage sites, exhibiting a discharge capacity twice its theoretical value by utilizing two different storage mechanisms.

A highly selective and active catalyst for the positional isomerisation of 2-butene into 1-butene has been developed by using a mesoporous silica, MCM-41. The yields of 1-butene as well as total conversion decrease when aluminium or lanthanum was added to the MCM-41 even though the amounts of acid sites increase. FT-IR spectra proved that the H site due to the silanol group may act as an active site for the positional isomerisation of 2-butene to 1-butene.

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.

Ordered mesoporous MnO, MnO4, Mn2O3 and MnO2 materials with 3-D pore structure were suc- cessfully synthesized via a nano-replication method by using ordered mesoporous silica, KIT-6 (Cubic Ia3d space group mesostructure) as the template under specific oxidation and reduction conditions. Notably, ordered mesoporous MnO with a crystalline wall (rock salt structure) was syn- thesized for the first time, to the best of our knowledge. The synthesis of the ordered mesoporous MnO was achieved by reducing the ordered mesoporous Mn3O4 under an H2 atmosphere, while preserving the ordered mesostructure and crystalline wall throughout the solid/solid transformation. All of the ordered mesoporous manganese oxides with different crystal structures and oxidation states demonstrated almost the same spherical-like morphology with several hundred nanometers of particles. The synthesized ordered mesoporous manganese oxides had uniform dual mesopores (2-3 nm, and ~20 nm) and crystalline frameworks with large surface areas (86-140 m2/g) and pore volumes (0.27-0.33 cm3/g).

Highly ordered mesoporous α-Mn2O3 with well-defined mesopores, high surface area, and high oxygen vacancy exhibits excellent catalytic activity toward H2O2 decomposition at low temperature.

Mesoporous materials constructed with different framework compositions such as iron oxides and manganese oxides, etc. have been successfully obtained by the impregnation with desired metal precursors into the bicontinuous cubic Ia3d mesoporous silica, crystallization to metal oxides at desired temperature and subsequent silica removal using NaOH aqueous solution.

Highly ordered mesoporous antimony-doped tin oxide (ATO) materials, containing different amount of antimony in the range of 0–50mol%, are prepared via a nanoreplication method using a mesoporous silica template. The mesoporous ATO materials thus obtained exhibit high electrical conductivity, high reversible capacity, superior cycle stability and good rate capability as anode materials for lithium-ion batteries, compared to those of pure mesoporous tin oxide. Amongst the ATO materials in this work, the mesoporous ATO material with 10mol% of antimony has highest discharge capacity of 1940mAhg-1 (charge capacity of 1049) at the 1st cycle, best cycle performance (716mAhg-1 at 100th cycle) and excellent rate capability, which are probably due to the enhanced electrical conductivity as well as reduced crystalline size.

Noise reduction in a 2.45GHz strapped magnetron oscillator is experimentally demonstrated by electric priming using anode shape modification. The sideband noise is reduced by approximately 15dB at the nominal operating current and by 28dB at the start-oscillation current; this is due to electron prebunching into the π mode, resulting from the modulation of the drift velocity of the electrons by an azimuthally periodic electric field. In this experiment, a 4.3kV–330mA half-wave rectified input power is employed.

This paper deals about three dimensional simulation of 10-vane strapped magnetron. A 10-vane strapped magnetron operating at 2.465 GHz for the microwave oven is modeled using three-dimensional particle-in-cell simulation code, called as MAGIC3D. The intention of this study to understand the origin of the leaked radiation from the microwave oven using 3D simulation.

Li4Ti5O12 with a cubic spinel structure (space group, Fd3(_)m) has a high redox potential at around 1.5 V vs. Li+/Li with a theoretical capacity of 175 mA h g−1.2 The negligible structural difference between pristine Li4Ti5O12 and lithiated Li7Ti5O12 at the two-phase equilibrium junction guarantees an outstanding electrochemical reversibility during the charge/discharge process.3 Furthermore, the high redox potential would prevent not only the lithium metal deposition on the anode at high current conditions but also the formation of the resistive solid electrolyte interphase (SEI) layer, which may lead to an active Li-ion loss and an increase of the cell impedance.4 No SEI formation at the surface of Li4Ti5O12 is a widely accepted argument from the literature point of view. However, in our previous report regarding the electrochemical study of the carbon-free Li4Ti5O12 electrode,5 we noticed the formation and dissolution of the SEI layer through the change in the intensity of Ti 2p XPS core peaks during the charge and discharge process. This fact led us to suspect the stability of Li4Ti5O12 vis-à-vis to the electrolyte in spite of its high redox potential. Despite the interesting properties of Li4Ti5O12, only few literature studies were reported on its reactivity to the electrolyte. Based on a detailed XPS study on the electrolyte/electrode interfaces in LiMn1.6Ni0.4O4/ Li4Ti5O12 system, Dedryvère et al. have reported the formation of organic and inorganic species on the surface of Li4Ti5O12 anode after cycling.6 However, they concluded that those species were first formed at the cathode and then, adsorbed on the surface of Li4Ti5O12 either by diffusion or by migration of organic cationic species. In addition, the lower voltage limit of Li4Ti5O12 anode couldn’t be also guaranteed to be over 1 V in their study because measuring the voltage of Li4Ti5O12 itself is impossible in two-electrode full cell. He et al. also pointed out the formation of SEI film on the Li4Ti5O12 electrode cycled between 2.5 and ~ 0 V vs. Li+/Li., but they mainly focused on the SEI formation occurred below 1 V.7 Moreover, in the aforementioned studies, the results were obtained only at room temperature cycling, and the effects of carbon conducting agent contained in the conventional Li4Ti5O12electrodes were neither considered nor clarified. In this report, for the first time, the Li4Ti5O12/ electrolyte interface is investigated at room and high temperature using the carbon-free Li4Ti5O12 electrode. The new electrode concept5,8 allows us to examine the reactivity of Li4Ti5O12 to the electrolyte and avoid any kind of parasite reaction which may be induced by the high-surface-area carbon conducting additive. Chemical changes at the surface of Li4Ti5O12 were investigated using a step by step X-ray photoelectron spectroscopy (XPS) analysis during charge/discharge cycling. The time-of-flight secondary ion mass spectroscopy (ToF-SIMS) study and scanning electron microscopy (SEM) observation were carried out to examine a quantitative and qualitative change in the surface chemistry and the electrode morphology after cycling, respectively. The differences between the carbon-free and carbon-containing Li4Ti5O12electrodes in terms of stability and cyclability were also discussed. [1] S.S. Zhang, J. Power Sources, 2006, 161, 1385. [2] T. Ohzuku, A. Ueda, N. Yamamoto, J. Electrochem. Soc., 1995, 142, 1431; L. Kavan, M. Gratzel, Electrochem. Solid State Lett., 2002, 5, A39. [3] K. Zaghib, M. Simoneua, A. Armand, M. Gauthier, J. Power Sources, 1999, 81-82, 300; G. Armstrong, A. R. Armstrong, J. Canales, P. G. Bruce, Electrochem. Solid-State Lett., 2006, 9, A139; A. N. Jansen, A. J. Kahaian, K. D. Kepler, P. A. Nelson, K. Amine, D. W. Dees, D.R. Vissers, M. M. Thackeray, J. Power Sources, 1999, 81-82, 902; T. Brousse, P. Fragnaud, R. Marchand, D. M. Schleich, O. Bohnke, K. West, J. Power Sources, 1997, 68, 412; T. Ohzuku, A. Ueda, N. Yamamoto, J. Electrochem. Soc., 1995, 142, 1431. [4] J. Christensen, V. Srinivasan, J. Newman, J. Electrochem. Soc., 2006, 153, A560; M. Winter, W. K. Appel, B. Evers, T. Hodal, K. C. Moller, I. Schneider, M. Wachtler, M. R. Wagner, G. H. Wrodnigg, J. O. Besenhard, Monatsch. Chem., 2001, 132, 473. [5] M. S. Song, A. Benayad, Y. M. Choi and K. S. Park, Chem. Commun., 2012, 48, 516. [6] R. Dedryvère, D. Foix, S. Franger, S. Patoux, L. Daniel and D. Gonbeau, J. Phys. Chem. C, 2010, 114, 10999. [7] Y. B. He, F. Ning, B. Li, Q. S. Song, W. Lv, H. Du , D. Zhai, F. Su, Q. H. Yang, F. Kang, J. of Power Sources, 2012, 202, 253. [8] C. J. Kim, N. S. Norberg, C. T. Alexander, R. Kostecki and J. Cabana, Adv. Funct. Mater., 2013, 23, 1214.

Highly ordered mesoporous TiO2 materials, exhibiting crystalline frameworks and various mesostructures, have been successfully obtained via nanoreplication using various kinds of mesoporous silicas...

Noble Gemini surfactants containing a siloxane moiety have been designed and successfully synthesized in the present study and are utilized as structure-directing agents for mesoporous metal oxides such as zirconia, titania, and vanadia. The siloxane moiety is believed to play an important nano-propping role during the surfactant removal by direct calcination, yielding thermally stable mesoporous metal oxides. It is also believed that the synthesis strategy described here can be applied to the synthesis of robust nanostructured materials such as nanoparticles and nanorods in addition to mesoporous materials.

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Highly ordered mesoporous SnO2 materials with residual silica species were successfully synthesized from a mesoporous silica template (SBA-15) via nano-replication and simple etching processes. A tin precursor, SnCl2·2H2O, was infiltrated spontaneously within the mesopores of the silica templates by melting the precursor at 353 K without using a solvent. After the heat-treatment of composite materials at 973 K under static air conditions, the controlled removal of silica templates using NaOH or HF solutions with different concentrations results in the successful preparation of mesoporous SnO2 materials, where the amounts of residual silica species are in the range 0.9–17.4 wt%. The residual silica species induce a nano-propping effect enabling the mesoporous SnO2 material (containing 6.0 wt% of silica species) to remain stable up to 973 K without any significant structural collapse. More importantly, the optimum amount of residual silica species (3.9–6.0 wt%) results in a dramatic reduction in capacity fading after prolonged charging–discharging cycles in Li-ion battery. The mesoporous SnO2 material with 3.9 wt% of silica species still exhibits a large capacity (about 600 mAh g−1) after the 30th cycle, which is probably because the residual silica species act as a physical barrier to suppress the aggregation of Sn clusters formed in the mesoporous SnO2 materials during the reversible lithium storage.