Hydroxyapatite fiber with high crystallinity was successfully fabricated by hydrothermal homogeneous precipitation synthesis with Ca(NO₃)₂·4H₂O and (NH₄)₂HPO₄ as precursors. Effects of the surfactants include cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and polyethylene glycol (PEG), and different amounts of them on the morphology and phase composition of the obtained products were investigated. Results show that the products obtained by using the three surfactants are all hydroxyapatite with minor CaCO₃ in some samples. The addition of both CTAB and SDS inhibits the growth of the fibers, leading to the coexistence of fibers and spherical aggregates. However, the addition of PEG can promote the growth of fibers to some extent.

C/C composites were fabricated by a rapid chemical liquid-vaporized infiltration (CLVI) processing. The fractured surfaces were observed by scanning electron microscope (SEM). In this paper, three
types of interfaces in the composites, the fiber-matrix interface within a tow, the interface between carbon cloths or bundles, as well as the interface between pyrocarbon laminar, were discussed.
Moreover, their influences on mechanical behavior of the composites were analyzed. In order to obtain high strength and pseudoductility, it is necessary for C/C composites to have proper interface bond
strength between fiber and matrix, smaller residual pores between carbon cloths or bundles, and proper gaps between pyrocarbon laminar within the matrix.

The research on the resonant characteristics of graphene is essential due to its excellence and vital significance for the future development and application of resonant sensors. Currently, the resonant characteristics of graphene are studied by experimental measurements and theoretical analysis, and the theoretical analysis is composed of the methods based on nano-scale mechanic and on classical mechanics. And the related theoretical researches on graphene are urgent because it is difficult to obtain the resonant characteristics of graphene accurately with experiments. In this paper, research methods, achievements and controversial problems are reviewed, including progress and consensus of the researches on the resonant characteristic of graphene e.g., the experiments of the resonant graphene sensor, the theoretical research methods and its classification, present situation, advantages, disadvantages, as well as the developing trend.

Monodispersed titanium dioxide nanoparticles were prepared by the hydrolysis of the titanium complex at 145℃ , the complex was obtained by the reaction of TiCl₄, with tri- ethanolamine. The crystalline phase and morphology of the nanoparticles were characterized by means of TEM and XRD techniques. The sizes of the particles can be regulated by changing pH values of the complex solution. The UV spectra of the complex solution were measured. The formation and hydrolysis of the complex were discussed.

Under the condition of keeping impulse amplitude of alternating voltage constant, microarc oxidation of
aluminium alloy in aqueous solution containing sodium silicate and sodium hydroxide was carried by means of alternating current power supply. It is
found that the current passing through the sample is divided obviously into five different stages with the oxidation time. The ceramic coatings prepared in
the different stages were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The result shows that the ceramic
coatings mainly contain γ-Al₂O₃, α-Al₂O₃ phases; the γ-Al₂O₃ and α-Al₂O₃ contents are close relative to oxidation time. The difference of γ-Al₂O₃ and α-Al₂O₃
contents between external layer and internal layer of the coating is mainly caused by the change of cooling rate of molten alumina in microarc zone.

Defect dipoles which have pronounced effects on properties of piezoelectric materials can be introduced either by partially modifying with acceptor impurities or volatizing of cation elements in perovskite lattice during sintering. The formation mechanism of defect dipoles and responses under external fields were reviewed in the present paper. Besides, the main physic mechanisms of ferroelectric aging, hysteresis loop abnormalities and electro- shape-memory effects in piezoelectric materials were discussed in detail from the defect dipoles viewpoints. Based on a defect mediated reversible domain switching mechanism, large recoverable electro-strain, as well as constricted hysteresis loops were obtained in unpoled aged ferroelectric crystals and/or ceramics, which indicated that aging was not always a detrimental effect, and may be promising for future novel applications. Furthermore, the defect dipole relaxation process was briefly described and the development trends of the high reliability piezoelectric actuators were proposed.

The microstructure and the electronic conductivity of plasma sprayed boron carbidecoating were studied. The results show that B₄C phase in the coating exists in two major structuregrained and flaky structures. Metal Fe as the impurity phase in the coating is the key factorresulting in the abnormality of electronic conductivity of B₄C coating. Another impurity phase,which consists of B, C and Fe elements, will decrease the microhardness of B₄C coating.

The Transparent and semi-transparent mixed inclusion is sometime found in the rutile single crystal grown by flame fusion methods. Moreover, parallel
stripes are shown in the inclusion. By means of XRD and SEM, (110) face of crystal with inclusion was investigated. It is shown that inclusion is
polycrystal, which consists of (110) orientated small crystal grains, some of them are affected by tension stress, the others by pressure stress.
On the other hand, parallel stripes in inclusion are layer-dislocation lines or crystal boundaries, which orientate [001], they are formed from cleavage along (110) face
due to thermal stress.

Silicon nanowire arrays were fabricated by metal-assisted chemical etching of single crystal silicon wafer. Then the silicon nanowire powder was obtained via ultrasonicating from silicon wafer and utilized as the anode electrode material of lithium ion battery. The effects of Ag catalyst deposition process and the subsequent anisotropic chemical etching on the formation of silicon nanowires were systematically investigated. The redistribution of Ag particles was found during the chemical etching. The large-area silicon nanowire arrays with proper length-diameter ratio were obtained by optimizing the concentration of AgNO₃, HF and H₂O₂ solution. The silicon nanowires exhibited the classical alloy-reaction plateaus of silicon and the specific capacity above 1800 mAh/g prior to the sixth cycle.

Porous monolithic SiO₂ materials were prepared via ambient pressure drying process with low cost silica sol as precursor and water as solvent. Cetyl trimethyl ammonium bromide (CTAB) was used as the surface modifier to get rid of the cumbersome process of solvent substitution which was necessary in the traditional ambient drying process. The densities, specific surface area and the average pore size of the obtained SiO₂ monoliths are in the range of 150-260 mg/cm³, 91-140 m²/g and 15-27 nm, respectively. The thermal conductivity was as low as 0.048 W/(m·K) at room temperature. This method greatly reduced the preparation cost as well as the operation difficulty and risk, which will largely promote the industrial production and application of porous SiO₂ materials.

The real graphite anode of lithium-ion battery is of evident non-isotropic characteristic due to its cascading graphite flakes. An ellipsoid particle-based simulated annealing method is developed to numerically reconstruct the three-dimensional microstructure of graphite anode. The reconstructed anode is a composite of three clearly distinguished phases: pore (or electrolyte), graphite and solid additive, well representing the non-isotropic characteristic of real graphite anode. Characterization analysis of reconstructed electrodes gives information such as the connectivity, the specific surface area of solid or pore phase, and the pore size distribution. The results show that the size of graphite ellipsoids has important effects on the characteristics of electrode: 1) larger size graphite ellipsoids result in larger mean pore size and smaller specific surface area in the reconstructed electrode; 2) changing the polar radius of graphite ellipsoid particles has more pronounced influence on the characteristics of electrode than has changing its equatorial radius.

Using agglomerated and sintered ZrO₂-7wt%Y₂O₃ (7YSZ) powders as raw materials, columnar thermal barrier coatings (TBCs) were prepared by plasma spray-physical vapor deposition (PS-PVD) at substrate temperature of 850 ℃. The microstructures of columnar coating were analyzed by field emission-scanning electron microscope (FE-SEM). Based on the theory of atoms together, the formation and growth process of 7YSZ nucleus were investigated and the deposition mechanism of columnar coating was also analyzed. Besides, under the temperature of 1200 ℃, the CMAS (CaO-MgO-Al₂O₃-SiO₂) corrosion of columnar 7YSZ coating was examined and its failure mechanism was also discussed. During the deposition process of columnar 7YSZ coating, the 7YSZ gas molecules were firstly absorbed on substrate, then through diffusion and migration, the critical nucleus formed rapidly. Besides, the critical nucleus further grew up forming crystal island by absorbing other molecules. Then after following four steps of island formation, union formation, channel formation and continuation, the columnar coating formed eventually. When above melting temperature, the CMAS could penetrate into porous columnar coating by capillary force and react with the 7YSZ coating. Finally, the cracks appeared in the coating due to thermochemical and thermomechanical interaction.

A naval hybrid buckypaper was fabricated by vacuum filtration method with monodispersed solution of Fe₃O₄ decorated carbon nanotubes (CNTs), which was easy to be infiltrated by resin and can be co-cured with polymer composites. The morphology, element composition, pore size distribution, and magnetic of hybrid buckypaper were characterized by field-emission scanning electron microscope (FE-SEM), energy dispersive spectrometer (EDS), Barret-Joyner-Halenda (BJH) and vibrating sample magnetometer. The electromagnetic parameters of CNTs composite and hybrid buckypaper attached CNTs composite were investigated in the frequency range of 8.2-18 GHz with wave guide method and the reflection loss can be calculated. The hybrid buckypaper with only absorbing thickness of 0.1 mm attached CNTs composite possesses much broader absorbing bandwidth and larger reflectivity than those of CNTs composite, nearly all of which reflectivity is below -10 dB in frequency range of 8.2-18 GHz and the minimum value is -43.18 dB at 15.42 GHz.

The Li-rich layered Li(Li_0.17Ni_0.2Mn_0.58Co_0.05)O₂ oxide was prepared by a spray-drying method. Subsequently, the surface modification with TiO₂(B) nanocrystallites (2wt%, 4wt%, 6wt%, 8wt%) was introduced into the Li-rich layered Li(Li_0.17Ni_0.2Mn_0.58Co_0.05)O₂ oxide by precipitation method. It is demonstrated that there is no obvious change in the crystallographic structure of the Li-rich layered Li(Li_0.17Ni_0.2Mn_0.58Co_0.05)O₂ oxide based on the analysis of XRD, SEM and TEM, while only the surface of the oxide is modified with TiO₂(B) nanocrystallites. It is indicated from DSC curves that the thermal stability of Li-rich layered oxide is obviously improved by the surface modification with TiO₂(B) nanocrystallites. Correspondingly, the large discharge capacity of 296.4 mAh/g and high coulombic efficiency of 84.5% are obtained at 0.1C rate (1C=300 mA/g) in the first cycle for the Li-rich layered oxide after the surface modification with TiO₂(B) nanocrystallites (4wt%). Moreover, the capacity retention after 100 cycles is increased from 69.5% for the pristine sample to 80.2% for the TiO₂(B)-modified sample. Even at 2C rate, the large discharge capacity of 166.5 mAh/g is still obtained for the TiO₂(B)-modified sample. Apparently, it is demonstrated from the above results that the surface modification with TiO₂(B) nanocrystallites can improve the thermal stability and electrochemical performance of the Li-rich layered Li(Li_0.17Ni_0.2Mn_0.58Co_0.05)O₂ oxide.

Based on photocatalysts, solar energy can be converted into the energy that human can directly utilize, so as to solve the problems such as the depletion of the Earth’s resources and the deterioration of living environments. The unique structure of g-C₃N₄ gives it good photocatalytic performance. Its development and utilization have been a research hotspot recently. Generally, g-C₃N₄ can be used in the degradation of pollutions, hydrolysis to generate hydrogen and oxygen, organic synthesis and oxygen reduction. However, in practical, its performance is not satisfactory. Researchers have tried many new methods to improve its photocatalysis, which include physical coupling modification, chemical bonding modification and microstructural modification. The review summarizes its photocatalysis and improving methods, briefly illustrates the catalysis mechanism, and presents detailed discussions and analysis on the existing problems as well as potential applications.

Nano/Micron Calcium Hexaboride (CaB₆) composite ceramics with different CaB₆ nanopowder additions were prepared under 1750℃, 32MPa for 5min in vacuum. Influences of CaB₆ nanopowders on morphology and mechanical properties of sintered bodies were investigated. Composite ceramic with 10wt% CaB₆ nanopowder addition has the highest compactness degree and mechanical properties, whose hardness, bending strength and fractural toughness are 92.6 HRA, 331.7MPa and 3.06MPa·m^1/2, respectively, better than those of CaB6 ceramics without nanopowder adding or those of reinforced by Ni as sintering additive. The proper amount of nano-particles filled in the micron grain boundaries and the formation of “inner crystal” result in the improvement of compactness and mechanical properties for the CaB6 sintered body.

Lithium-sulfur battery, fabricated with metal lithium as anode and sulfur as cathode, has received more attention as the most promising high energy power sources due to its high theoretical energy density (2600 Wh/kg). However, there are some serious and unavoidable problems for lithium-sulfur battery based on the dissolution-deposition processes in organic electrolyte, including serious structure change of metallic lithium anode, the lower utilization and poor cycle performance of active materials, which become a big barrier for the research and development of lithium-sulfur battery. The current status, problems and challenges of lithium-sulfur battery are summarized, including the sulfur-based cathode composites, electrolyte and lithium anode.

(Ca, Cr) co-doped YAG ceramics were synthesized by high temperature solid state reaction. The effects of Ca²⁺ and Cr³⁺ ions doping on the infrared emission properties of YAG ceramics were investigated. X-ray diffraction results showed that the phase composition of the prepared samples were yttrium aluminum garnet, which indicated that the Ca²⁺ and Cr³⁺ irons were incorporated into the crystal lattice of yttrium-aluminate garnet structure. Infrared absorption results showed that the infrared absorptivity of the (Ca, Cr) co-doped samples was 0.90, which was 29 times higher than that of the pure YAG sample (0.03). The band gap of YAG ceramics were decreased 1.77 eV by Ca²⁺ and Cr³⁺ co-doping based on calculation of the absorbance test results. Therefore, the absorption of the free carrier was improved, which is the main reason why the (Ca, Cr) co-doping YAG ceramics have a high emissivity in near infrared wavelength.

The poisoning phenomenon on the surface of ITO target during DC-Magnetron sputtering process was investigated. XRD, EPMA and LECO oxygen analyzer were used to study the poisoning mechanism and the factors leading to poisoning were analyzed. The result shows that In₂O₃ is decomposed into In₂O and O₂. This reaction on the surface of ITO target is the reason causing the poisoning phenomenon.

A new generation of Li-rich solid solution materials is cathode material xLi₂MnO₃·(1-x)LiMO₂ (M= Co, Fe, Ni_1/2Mn_1/2…) because of its excellent electrochemical performance. The series of Li-rich cathode material exhibits high capacity and excellent cycleability, which may be associated with a new electrochemical charge-discharge mechanism, It is proposed to satisfy the high energy Li-ion batteries. The structure, synthesis methods and electrochemical properties of the Li-rich cathode materials were reviewed in this paper. The factors affecting the electrochemical properties of the cathode materials were discussed, and the recent research progress on improving the electrochemical performance of Li-rich cathode materials was summarized. In addition, the characteristics and the trend of different Li-rich cathode materials were described.

A new type of bioactive calcium
phosphate cement with an excellent property of anti-washout for bone replacement was prepared by using cellulose as additive and non-aqueous solvent as liquid. The property of anti-washout, physical chemistry performances, hydration products and the biocompatibility were investigated. The results indicate that the improved CPC has an excellent anti-washout property and can be easily shaped as well as injected. The addition of the cellulose does not have obviously effect on the setting time and compressive strength of the CPC hardened body. The cultural cells are attached, dispersed and preferentially proliferated on the surface of the improved CPC. The fabricated biomaterials can be used as the filler of the bone defect or vertebroplasty or kyphoplasty in micro invasive surgery.

The preparation, structure and properties of ferroelectric nanometer sized powders, nanocomposites, and nanoceramics were introduced. The change of structure and properties caused by the reduction
of particle size and pertinent mechanisms were discussed. Transparent nanocomposites were expected to be applied as the optical memories, optical computer, etc devices, while the nanoceramics can be
widely used to improve the characteristic parameters of current capacitors due to the greatly enhanced dielectric permittivity, breakdown voltage, ageing-resistivity, mechanical strength, etc. Better quality
of devices will be obtained by using the nanosized powders.

Graphene has attracted much interest in recent years due to its unique and outstanding properties. Different routes to prepare graphene have been developed and achieved. Preparation methods of graphene used in recent years are intensively introduced, including micromechanical cleavage, chemical vapor deposition, liquid/gas- phase-based exfoliation of graphite, epitaxial growth on an insulator, chemical reduction of exfoliated graphene oxide, etc. And their advantages and shortcomings are further discussed in detail. The preparations of graphene are also prospected.

Zinc ion battery, a new type of aqueous secondary batteries proposed in recent years, can deliver high energy and high power density. Meanwhile, safe and efficient discharge processes, cheap and nontoxic electrode materials, and easy fabrication are the advantage of Zinc ion battery, showing great practical value and developmental prospects in the field of scale energy storage. In this paper, the development and exploration of aqueous zinc ion battery are reviewed. Also the advantages and challenges of the zinc anode are summarized. Moreover, this paper analyzed the electrochemical properties and reaction mechanism specifically. In addition, the development of cathode materials is predicted by analyzing the insertion and extraction of multivalent ions.

Microstructure engineering is an effective avenue for tuning the thermal and electrical transports to op-timize thermoelectric (TE) properties. Thermoelectric composites with nano-particle dispersion have been success-fully developed by using extrinsic or in-situ formation methods. The lattice thermal conductivity can be depressed by the scattering effects of nano particles to the medium-long-wavelength phonons. The enhanced electron density of states at the Fermi level and the carrier filtering effects caused by the nano-sized grain boundary are also positive for enhancing Seebeck coefficients. The mixing, in-situ oxidation and phase-separation precipitation process supply possibility to realize the nano-particle dispersed structure for different material systems. This paper reviews the re-cent progress of the research on nano-structured and nano-composite thermoelectric materials. The effects of the nano-dispersion on the electrical and thermal transports will be also discussed.

Graphene has recently attracted much interest in material field due to its unique two-dimensional structure and outstanding properties. Various preparation methods of graphene are briefly compared. The physical and mechanical properties of graphene are then introduced. Graphene-based composite becomes one of the most important research frontiers in the application of graphene. A comprehensive review is presented to introduce the latest progress of the graphene related composites, including graphene-polymer composites and graphene-based inorganic nanocomposites, especially introducing the fabrication methods and outstanding performances of the bulk metal-matrix/ graphene composites.

As the second essential trace element in human body, copper plays vital roles in metabolism and antimicrobial. Therefore, synthesis of copper-substituted hydroxyapatite (Cu-HA) is expected to create bioceramics with improved biological and antimicrobial properties. In this study, Cu-HA was prepared by hydrothermal reactions using Ca(NO₃)₂∙4H₂O, Cu(NO₃)₂∙3H₂O and Na₂HPO₄∙12H₂O. Products were characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction, Fourier transform infrared spectroscope and atomic absorption spectrometry. Results show that copper is incorporated into the HA crystals. Correspondingly, the products retain HA structure but their morphologies transform from ribbons to flower-like microspheres. Moreover, when Cu/(Cu+Ca) (molar ratio) of the reaction solution is greater than 0.05, the thermal stability of the HA product is decreased.

MXene is a new family of two-dimensional transition metal carbides or carbonitrides with graphene-like 2D morphology. The chemical formula of MXene is M_n+1X_nT_z, where M is an early transition metal, X is C and/or N, T stands for surface-terminating functional groups like F^-, OH^-, O^2-, etc., and n = 1, 2, or 3. It can be achieved by selective etching of the A element from the MAX phases, and HF is an etchant mostly used. First-principles calculations about MXene have been performed to reveal the structure and properties. MXene has also been found to have a unique two-dimensional layered structure, large specific surface area and good electrical conductivity, stability, magnetic and mechanical properties, and thus it is promising in many fields, including energy storage, catalysis and adsorption. This article reviews the quite recent progress of MXene based on theoretical and experimental considerations, especially its structure, synthesis, and applications. Finally, the suggestions about existing challenges and future developments are proposed. MXene is expected to be used for more various applications with further extensive research.

Porous-Bi₂WO₆ was synthesized by a hydrothermal process. The phase composition, morphology, surface area/pore size distribution and optical properties of as-synthesized Bi₂WO₆ sample were investigated by X-ray diffraction (XRD), filed-scanning electron microscope (FE-SEM), transmission electron mcroscope (TEM), energy dispersive spectrometer (EDS), UV-Vis absorption spectrum (UV-Vis-DRS), and low-temperature N₂ adsorption/desorption techniques. Furthermore, the photocatalytic oxidative desulfurization (Photo-ODS) activity of as-synthesized Bi₂WO₆ samples was also investigated. The experimental results reveal that reaction temperature and reaction time have a significant effect on the morphology and structure of Bi₂WO₆ under the strong acidic medium. After 2 h of reaction at 190℃, the as-obtained sample exhibits a novel nest-like 3D Bi₂WO₆ microcrystal with scales of 3-4 μm. HR-SEM reveals that the 3D nest-like Bi₂WO₆ microcrystal composes of many small secondary nanoplates. XRD and EDS results confirm that the as-synthesized D nest-like Bi₂WO₆ microcrystal is orthorhombic pure-Bi₂WO₆. N₂ adsorption/desorption isotherms and the pore distribution result show that nest-like 3D Bi₂WO₆ microcrystal has pores in the size of 6-8 nm and the BET surface area is calculated to be as much as 17.49 m²/g. The photocatalytic experimental result illustrates that as-synthesized 3D nest-like porous Bi₂WO₆ microcrystals exhibit an excellent photocatalytic performance to photocatalytic oxidative desulfurization for simulated fuel oil under sun-like light irradiation. Under the conditions of 100 mL/min air flow, 1.2 g/L photocatalyst amount, and visible-light irradiation for 180 min, the desulfurization rate of simulated fuel oil reaches 91.2%, and the stability of photoctalyst is also good.

orous nickel oxides were prepared by hydrolysis and furtherheat treatment of nickel acetate in air at 300℃. An new type electrochemical capacitor system with
an asymmetric configuration was demonstrated. The nickel oxides prepared and active carbon wereapplied to the positive and negative electrodes respectively. These oxides can provide a specific capacitance of
240F/g, and maintain high utilization at high rates of discharge (i.e., high power density).The maximum operational voltage of the capacitor can be improved effectively and high power discharge attained.

CuAlO₂ films were prepared by pulsed laser deposition (PLD) on Al₂O₃(001).And the effect of deposition laser energy on the microstructure, morphologies and optical properties of the films were studied. The in-situ deposited films were amorphous in the deposition laser energyof 100-180mJ. After ex-situ annealed in N₂ atmosphere at 900℃ for 1 h, all the films were single phase CuAlO₂with c-axis orientation and the crystal sizes were about 49nm. With the increase of deposition laser energy,the film thickness and surface particle sizes increased, while the visiblelight transmittance decreased. Room-temperature photoluminescence measurements of the CuAlO₂ films deposited with laser energy of 100mJ and 180mJ only showed an ultraviolet near-band-edge emission peak at 350 nm (around 3.5eV) in the range of 325-650 nm, which originated from the generation and recombination of electron-hole pairs, namely, excitons. This observation indicates the existence of direct transition-type band gap of thismaterial, which is favorable for the optoelectronics applications such aslight-emitting diodes (LEDs).

Development of perovskite solar cell is very fast in recent years due to its low cost and high photoelectric conversion efficiency. The perovskite solar cell is generally composed by the compact nanocrystalline layer, light absorber CH₃NH₃PbX₃ (X= Cl, Br, I), hole transporting layer, and counter electrode. Among these components, the light absorber species and its preparation techniques, hole transporting material species and the structure design of the device are the most important factors, which directly affect the photovoltaic performances of perovskite solar cells. This paper summarizes the effect of the light-absorbers, hole transport materials, processing parameters, and device structural design on the photovoltaic properties of perovskite solar cells according to recent research progresses in this field. And the development trends of the perovskite solar cells are proposed.

Diluted magnetic semiconductors (DMSs) are new functional materials formed by doping a few percentages of magnetic ions in nonmagnetic semiconductors. Recently, the ferromagnetism origin and magnetism theory are the research hotspot in the field of DMSs. It is still unclear how the ferromagnetism is induced between the doped magnetic ions and the carriers. In this paper, the recent progress in magnetism theory was reviewed. The typical theories including RKKY, mean field theory, double exchange and bound magnetic polaron were elucidated in detail. The hotspot of experimental, theoretical research and existing problems were evaluated.

Crack-free and hydrophobic SiO₂ aerogels were repeatedly obtained at subcritical condition dried with iso-butanol, which were modified by TMCS. The microstructure
and properties of the silica aerogel were measured by pore size distribution, SEM, IR, contact angle and BET techniques. The results show that the SiO₂
aerogels prepared at subcritical conditions have classical nano microstructure(mean particle size: 10nm; mean pore radius: 14.5nm), large specific surface area about 708.3m²/g). Because of the significant reduction of drying pressure from
6.4MPa to 2.3MPa, the manufactory price of the silica aerogels can be reduced. On the other hand, it is hydrophobic, which can be used widely. So it is more
suitable for large scale production and application.

Molybdenum disulfide (MoS₂), a new binary transition-metal compound,has attracted much attention due to its unique physical and chemical properties. MoS₂ with different morphology structures were firstly reviewed, including inorganic fullerene-like, sphere-like, flower-like, wire, plate, rod, tube and so on. And then, the methods used to prepare MoS₂ nanomaterials were discussed, including chemical vapor deposition method, sulfurization process, exfoliation, electrodeposition, hydrothermal method, and solvothermal method. The applications of MoS₂ nanostructures in various fields were also summaried, such as lubrication, catalytic and photoelectric devices. Finally, the outlook for the research of this molybdenum disulfide nanomaterial was proposed.

Porous Si₃N₄ ceramics with high strength, uniform structure and relative high porosity were
obtained by gelcasting. The mechanical performances and micro-structure of the porous Si₃N₄ ceramics were studied and the reasons were
discussed. It was showed that using proper techniques, green bodies with high strength, uniform structure and good machining proparey
could be got. Results show that the sintered porous Si₃N₄ ceramics have strength more than 150MPa and porosity up to 50%. SEM shows that porous are formed
by the banding-up of pillar β-Si₃N₄. The uniform porous distribution and pillar structure are the main reasons for good mechanical performances.

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Silicon nitride thin films (SiN_x) were prepared on silicon wafers from SiHCl₃ (TCS)-NH₃-N₂
system via low pressure chemical vapor deposition (LPCVD) from 730℃ to 830℃ in a hot-wall horizontal tubular reactor.
By spectroscopic ellipsometer and Atomic Force Microscope (AFM), the growth rate and surface morphology of the films were investigated with various
deposition parameters, including total pressure, substrate temperature and reactive gas feed ratio. As total pressure increases, growth rate increases
at lower pressure and then decreases at higher pressure. The dependence of growth rate on substrate temperature is similar to that of total pressure.
However, as NH₃/TCS ratio increases, growth rate gradually increases and eventually amounts to a constant. The apparent activation energy of the
reaction from 730℃ to 830℃ is about 171kJ/mol. AFM results reveal that lower growth rate is favor to improve film uniformity. SiN_x
films with promising surface roughness can be prepared under appropriate deposition conditions.

Aluminum titanate powder was synthesized by nonhydrolytic and hydrolytic sol-gel method, respectively. The sol-gel process, the phase transformation and the sintering properties of powders were studied by TG-DTA, XRD, FT-IR and SEM analysis. The results show that during the hydrolytic sol-gel process, the Al³⁺ ions mostly exist in the interspace of Ti—O—Ti network. As a result, only rutile and corundum are separated from the hydrolytic gel, the Al₂TiO5 has to be synthesized at 1350℃. Comparatively, the gel network is formed through the polymerization reaction of Al³⁺ and Ti⁴⁺ ions in nonhydrolytic sol-gel process, these ions occupy the similar position to build the gel network together. Therefore, the armorphous phase is directly crystallized at 750℃ as aluminum titanate. The particle size and specific surface area of Al₂TiO₅ powders prepared by hydrolytic sol-gel method are 1－2μm and 3.2m²/g. It is dropped to 0.1－0.3μm under nonhydrolytic sol-gel method, while the specific surface area of the powders is 35 times of hydrolytic sol-gel sample. The bending strength of the sintered Al₂TiO₅ ceramic prepared by nonhydrolytic sol-gel method is 2.3 times of hydrolytic sol-gel sample, which is only 7.2MPa. It indicates that the properties of Al₂TiO₅ powders prepared by nonhydrolytic sol-gel method are better than that of hydrolytic sol-gel sample.

MoS₂/C composites were prepared by a simple CTAB assistant thermal reduction method using sodium molybdate, thiourea and CTAB as starting materials. The samples were characterized by XRD, SEM, TEM, and TG. It is confirmed that the amorphous carbon is partially inserted into the interlayer spaces of molybdenum disulfide and inhibits the accumulation of (002) plane. Meanwhile, the electrochemical properties were studied in detail. As a consequence, the MoS₂/C composites have better electrochemical performance than pure MoS₂. The composite synthesized by adding 0.025 g CTAB shows the best electrochemical performance. The initial discharge capacity was 730 mAh/g and a stable capacity above 415 mAh/g was retained for 100 cycles tested at 100 mA/g. At last, the possible growth mechanism of the MoS₂/a-C composites and the influence of different micro-morphology are also calculated.