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.

Two types of Na-doped and Na/Se co-doped polycrystalline, sintered samples of p-type AgSbTe₂ thermo- electric compounds were prepared from high purity elements by a melt-quench technique followed by spark plasma sintering (Ⅰ: with excess Na or Na/Se, AgNa_0.01SbTe₂, AgNa_0.01SbTe₂Se_0.04; Ⅱ: replacing corresponding elements by Na or Na/Se, Ag_0.99Na_0.01SbTe₂, Ag_0.99Na_0.01SbTe_1.96Se_0.04). The impacts of Na-doping, Na/Se co-doping and doping form on electrical and thermal transport properties were investigated. Meanwhile, by comparing the thermoelectric performance of samples with different kinds of doping form, the optimal doping method is obtained. That is Na replacing Ag, Se replacing Te with appropriate amount of excess Se. Due to the elevation of Seebeck coefficient by Na-doping and optimization of electrical and thermal conductivities by Se-doping, a maximum of ZT merit of 1.4 is achieved at 620 K for sample Ag_0.99Na_0.01SbTe_1.96Se_0.04, representing a 17% enhancement with respect to the undoped sample at the same temperature.

Anode-supported solid oxide fuel cells (SOFCs) composed of NiO-SDC (Sm_0.2Ce_0.8O_1.9) composite anode, thin tri-layer electrolyte, and La_0.6Sr_0.4Co_0.8Fe_0.2O₃ (LSCF)-La_0.9Sr_0.1Ga_0.8Mg_0.2O_3-δ (LSGM) composite cathode were fabricated. The thin 11μmSDC/15μmLSGM/13μmSDC tri-layer electrolyte was prepared by centrifugal casting and co-firing technique. Cell tests in air as oxidant and humidified hydrogen as fuel show a maximum power density of 0.92W/cm² at 800℃. However, the open-circuit voltage (OCV) of these cells is 0.89V which is lower than the Nernst potential. The above result is due to electronic conductivity in the LSGM layer, resulting from Ni impurities that entered during co-firing with the NiO-SDC anode. While the SDC buffer layers are introduced as buffer layers, impedance measurements indicate that both the ohmic resistance and the polarization resistance dominate the cell performance.

Higher manganese silicides (HMS) bulk materials with the nominal compositions of MnSi_x (x = 1.60, 1.65, 1.68, 1.73, 1.81, 1.85) were prepared by arc-melting, annealing and spark plasma sintering. The phase structures and morphologies of the samples were investigated, and their thermoelectric properties were measured from 300℃ to 600℃. The analyses of phase compositions revealed that the intensity of X-ray diffraction peaks was firstly enhanced and then weakened along with x value increasing. The phase composition were of HMS and MnSi for x<1.73 samples, and were of the HMS and Si for x≥1.73 samples. It was shown that the thermoelectric properties of the samples were affected strongly by the metallic MnSi phase and the semiconducting Si phase. The electrical conductivity decreased continuously, while the Seebeck coefficients increased with x value increasing. In addition, the thermal conductivity decreased firstly and then increased with x value increasing. Furthermore, it was showed that the thermal conductivity remained constant at lower temperature and then increased sharply because of the contribution of electron thermal conductivity at temperature higher than 450℃. The MnSi_1.68 sample had the highest dimensionless figure of merit ZT 0.36 at 400℃, as a result of its highest electrical performance (power factor) and moderately low thermal conductivity.

Rare-earth zirconates with a pyrochlore structure have attracted great attention for potential application in thermal barrier coating systems. In the present work, Sm₂Zr₂O₇ coatings were deposited by atmospheric plasma spraying technology. Their microstructure, thermo-physical and mechanical properties were examined, and compared with that of 8wt% Y₂O₃ stabilized ZrO₂ coatings which was deposited under the same plasma spraying conditions. X-ray diffraction result shows that the as-sprayed Sm₂Zr₂O₇ coating exhibits a defective fluorite structure. The thermal conductivity of Sm₂Zr₂O₇ coating measured at 800℃ is 0.44W/(mK), about 40% lower than that of 8wt% Y₂O₃ stabilized ZrO₂ coating, but the expansion coefficients of both coatings are similar. The Sm₂Zr₂O₇ coating exhibits lower bending strength, microhardness and elastic modulus compared with 8wt% Y₂O₃ stabilized ZrO₂ coating.

Ba_0.25Sr_0.75Al₂Si₂O₈ (BSAS) as environmental barrier coating (EBC) was coated on the 2D C_f/SiC substrate using slurry-brushing process. The water-vapor corrosion resistance of C_f/SiC and C_f/SiC-BSAS were studied in 50%H₂O-50%O₂ water vapor under atmospheric pressure and static atmosphere at 1250℃, respectively. The results show that the dense BSAS coating with free cracks can be prepared by slurry-brushing method followed by heat-treatment at 1350℃ in high purity argon. The coating thickness approximate to 15μm after pasted once, and can reach 50μm after pasted for three times. The weight and flexural strength of C_f/SiC-SiC decreases greatly, while the weight of C_f/SiC-BSAS has no obvious change and the flexural strength retention is over 90% after corroded for 100 h.

Graphene has no oxygen groups on its surface, resulting in a poor dispersion in water. The synthesis of graphene with high water solubility is popular nowadays. In this study, the oxygen content of graphite oxide was adjusted by a low-temperature and high-vacuum expansion process, the resultant graphene sheets exhibited the smallest thickness of about 1.7 nm and size of 1.0 um. The results indicated that prepared graphene could be stable in neutral aqueous solution without surfactant, and the solubility of the water-soluble graphene was 0.07 mg/mL. In addition, the electrical conductivity of the graphene film of around 1000 S/m was higher than many reported noncovalent graphene films.

With C₃H₆ as the precursor, N₂ as the carrier gas and high density 3D carbon fiber braided preform, the plate of C/C composites was fabricated by the fast CVI process. Influence of gradient pressure and other factors of process on the sealed pores in C/C composites were analyzed, and the morphologies were characterized by scanning electron microscope (SEM) and polarized light microscope (PLM) in detail. The formation mechanism of sealed pores and the transformation of density in high density preform in the densification process are simply analysized. The experimental results show that the sealed pores can be reduced by multi-stage CVI process and the density of the C/C composite are improved from 0.94g/cm3 to 1.82g/cm³ after 250 h CVI process.

With composite powders of Ti-B₄C-C and Ti-B₄C-C-Al systems as reactants, Ti(C, N)-TiB₂ -based composite ceramic preforms were prepared by self-reactive spray forming technology. XRD, SEM, EDS and TEM were used to investigate the influence of 5wt% Al addition on the structure and properties of the preforms. It was shown that the performs made from Ti-B₄C-C system were mainly composed of TiC_0.3N_0.7 and TiB₂, with by-product phase of TiO₂. Relative density, Vickers hardness, flexural strength and fracture toughness of Ti-B₄C-C preforms were 97.2%, 17.3GPa, 387MPa and 6.0MPa·m^1/2, respectively. By adding 5wt%Al in the sprayed system, the by-product of the preforms was the desirable phases of Al₂O₃ and Ti₃Al, not TiO₂, though the main phases of Ti-B₄C-C-Al preforms remained to be TiC_0.3N_0.7 and TiB₂. The length to diameter ratio of the TiB₂ grains increased obviously. As a result, relative density, Vickers hardness, flexural strength and fracture toughness of Ti-B₄C-C-Al preforms as-cended to be 97.7%, 20.6GPa, 425MPa and 7.3MPa·m^1/2, respectively. The additive Al effectively restrained the oxidation of Ti in the spray forming process, which improved the mechanical properties of the preforms greatly.

Surface morphology of the ceramic coatings can be modulated by gas evolution on anodes during micro arc oxidation (MAO) processes. A novel technique to enhance gas evolution using Na₂CO₃-containing solution was proposed. MAO ceramic coatings were fabricated on AZ31 magnesium alloy using Na₂CO₃ as a special additive in Na₃PO₄+KOH +NaF base electrolyte. The effects of Na₂CO₃ addition on the reaction of gas evolution near the anode, morphology modulation and chemical composition were investigated by using GC-MS, SEM, XRD and FTIR, respectively. The results show that both O₂ and CO₂ are evolved from the anode with Na₂CO₃ addition during MAO process. MgCO₃ is found in the coating during the anodic oxidation before MAO, while only MgO is detected in the coating after MAO process. It is attributed to the decomposition of MgCO₃ to MgO and CO₂ due to local high temperature. Na₂CO₃ addition has slight effect on the microstructure of the coating and MgO is the main phase no matter whether Na₂CO₃ is utilized. With the addition of Na₂CO₃ the number of larger-size pores decreases and porosity in the coatings increases.

The nanophosphor Eu_0.12Y_1.78Ca_0.10O_3-δ was synthesized by homogeneous precipitation method under ultrasonic condition. The structures, composition and morphology of the nanophosphor Eu_0.12Y_1.78Ca_0.10O_3-δ were characterized by X-ray diffraction(XRD), energy dispersive spectrometre(EDS), inductively coupled plasma atomic emission spectrometry(ICP-AES) and transmission electron microscope(TEM). The synthesis kinetics of nanophosphor Eu_0.12Y_1.78Ca_0.10O_3-δ was investigated using differential thermal analysis and thermo gravimetric analysis (DTA-TG) at different heating rates in argon. The results show that the Eu_0.12Y_1.78Ca_0.10O_3-δ is body-centered-     cubic-structured spherical nano-polycrytalline with grain size of 20nm. The precursor of nanophosphor Eu_0.12Y_1.78Ca_0.10O_3-δ is Y(OH)₃ with hexagonal phase structure. The average apparent activation energy of the three reaction stages of precursor is calculated to be 102.06, 488.00 and 302.74kJ/mol by using the Doyle-Ozawa and Kissinger methods, respectively. The reaction order and frequency factor are determined by Kissinger method. The kinetics equations of each reaction stage is deduced as dα/dt=8.86×10⁸e^-12280/T(1-α)^1.36; dα/dt=4.05× 10³³e^-58700/T(1-α)^1.32; dα/dt=7.14×10¹⁹e^-36410/T(1-α)^1.27.

A blue phosphor, KNaCa₂(PO₄)₂:Eu²⁺, was prepared by the high temperature solid-state method, and its luminescent characteristics were investigated. The spectral characteristics show that it can be effectively excited by near ultraviolet light (400 nm), and exhibits blue light (470 nm). The crystallographic sites of Eu²⁺ in KNaCa₂(PO₄)₂ are calculated by van Uitert formula. In KNaCa₂(PO₄)₂:Eu²⁺, the emission band centered at 461 nm originates from the Eu²⁺ center of the eight compounds, and the emission band centered at 502 nm originates from the Eu²⁺ center of the six compounds. The influence of Eu²⁺ concentration on the emission intensity of the phosphor is investigated. The result shows that the emission intensities firstly increase with the increase in Eu²⁺ concentration, reach a maximum at 1mol% Eu²⁺, and then decrease. The concentration quenching mechanisms are the d-d interaction by Dexter theory.

CdHgTe alloyed quantum dots (QDs) were directly synthesized in aqueous solution by heating a mixture of CdCl₂, HgCl₂ and NaHTe in the presence of thioglycolic acid as stabilizer. The obtained QDs were characterized by fluorescent spectroscope, fourier transform infrared spectroscope (FTIR), X-ray powder diffraction (XRD) and transmission electron microscope (TEM), respectively. The results show that the technique lead to the formation of CdHgTe alloyed QDs with broad fluorescence full-width at half-maximum (70-90 nm), moderate photoluminescence quantum yield (1.5%-6.7%), and a broad emission spectra tunable from 536 nm to 688 nm. The water-soluble alloyed QDs with thioglycolic acid modification for CdHgTe are of zinc-blended crystal structure in a sphere-like shape.

With tetrabutyl orthotitanate (TBOT) as Ti source, La(NO₃)₃·6H₂O as La source and octadecylamine as a template, La-doped mesoporous TiO₂ microspheres were prepared by ultrasonic-hydrothermal method. The obtained samples were characterized by XRD, XPS, TEM, BET, UV-Vis, IR and FL.The results revealed that the appropriate molar fraction of La dopant could decrease crystalline size, increase specific surface area and weaken fluorescence intensity of mesoporous TiO₂. Compared with P25, the gap adsorption edge of mesoporous La³⁺/TiO₂ exhibited a little red shift and slightly narrowed their band gaps. For mesoporous La³⁺/TiO₂ (2.0 at%), the specific surface area and the average pore diameter were 132.7 m²/g and 8.67 nm, respectively. Furthermore, the degradation ratio of methylene blue to mesoporous La³⁺/TiO₂ (2.0at%) was up to 98.5%, which exhibited the best photocatalytic activity with the initial concentration of 40 mg/L for 120 min.

The composite photocatalysts combining high adsorptive capacity with enhanced photocatalytic efficiency are expected to be more efficient catalysts for the pollutant removal in the wastewater. TiO₂ nanotubes (TNTs) were synthesized via hydrothermal method using Degussa P25 titania as raw material. The Pt-loaded TiO₂ nanotubes/nanocrystals composite photocatalysts (Pt/TNNs) were prepared via one-step synthesis method involved the vapor phase hydrolysis setup, where TNTs were added into the ethanol solution containing chloroplatinic acid and citric acid (as the reductant). During the water vapor treatment, some of the nanotubes were transformed into anatase TiO₂ nanocrystals and a small amount of TNTs were kept as the tubular morphologies, thus the composite had a higher adsorptive capacity. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscope and N₂ isothermal adsorption-desorption. Results showed that the Pt nanoparticles with crystallite size of 4 nm were uniformly dispersed onto the surface of remaining TNTs and anatase TiO₂ nanocrystals with crystallite size of 8 nm derived from the transformation of TNTs, and the composite photocatalysts kept a specific surface area of more than 216 m²/g. The photocatalytic activity of Pt/TNNs was evaluated by the degradation rate of acid red G (ARG) and methylene blue (MB) under UV irradiation. The results showed that the pristine TNTs had good adsorptive ability but very poor photocatalytic activity. After loading with Pt nanocrystals, Pt/TNNs obtained via water vapor treatment at 120℃ exhibited much higher photocatalytic efficiency compared with the pristine TNTs.

Bismuth ferrite (BiFeO₃) powders were hydrothermally synthesized by using Bi(NO)₃^.5H₂O and Fe(NO)₃^.9H₂O as starting materials, and KOH used as a mineralizer. The large-scale polyhedral BiFeO₃ particles were obtained by controlling KOH concentration, heating and cooling rate. It was found that the large-scale polyhedral BiFeO₃ particles were synthesized favorably at the high KOH concentrations and an appropriate cooling rate was an important factor for synthesis of high crystallinity BiFeO₃ particles. The quasi-cubic and truncated cubic particles of high crystallinity were obtained at the KOH concentration of 6 and 8 mol/L with the cooling rate of 0.2℃/min, respectively. The rough cubo-octahedron, truncated octahedron particles were obtained by changing the cooling rate to 0.1℃/min. The rough truncated cubic particles with pores were obtained by changing the cooling rate to 2℃/min. Morphologies evolution of large-scale polyhedron bismuth ferrite particles were observed by scanning electron microscope. The formation mechanism of the regular morphologies was also discussed.

The porous ceramics were prepared by the foam impregnation technology using Al₂O₃-MgO-P₂O₅ as binder. Porous morphology, crystalline phase, porosity, and mechanical property were investigated by using scaning electron microscope (SEM), X-ray diffraction (XRD), Archimedes drainage method, and compression tests. It was found that Al₂O₃-MgO-P₂O₅ phosphate promoted the sintering of ceramics, and improved coating of ceramic slurry over the foams uniformly. The obtained ceramics have connective, uniform pore structures with macro-pores of about 100-500μm in diameter and micro-pores of about 3μm in diameter. Their average porosity and compressive strength were 85.9%±1.6% and (1.04±0.15) MPa respectively. Although sintered porous ceramics were polyphosphates composed of HA, β-Ca₂P₂O₇ and a few phases including Al and Mg. They had no cytotoxicity and provoked the proliferation and differentiation of marrow stromal stem cells in vitro. Thus it can be concluded that this kind of porous ceramics has good cellular affinity and cytocompatibility.

YBCO films doped with Zr or substituted by Gd element were prepared by fluorine-reduced metal organic deposition (MOD) on LAO single crystal. The influences of different dopants on in-field critical current density (J_c) of YBCO films were investigated. It is found that the J_c values of YBCO films in high field were enhanced drastically through substituting Y site by Gd element partially, while the J_c values of YBCO films in low field are not enhanced. The J_c values of YBCO films in low field are improved significantly by adding extra Gd element into YBCO film because of the formation of rare earth oxide particles in YBCO film. But in high field, it has slight effect on J_c values. It is an effective method to improve the property of YBCO film by adding Zr-contained compounds into YBCO film to form BZO nano particles, which can enhance J_c values of YBCO film in low field and in high field. Finally, the high performance Y_0.5Gd_0.5BCO film incorporated with BZO nano particles was prepared. The max pinning force (F_p(max)) is up to 16GN/cm³, as higher as 4 times of that of pure YBCO film. J_c values of Y_0.5Gd_0.5BCO+Zr film at 65K reach 1.31MA/cm²(3T) and 87.7kA/cm²(7T).

The SiO₂ and TiO₂ Sol were prepared via Sol-Gel process using tetraethyl orthosilicate(TEOS) and tetrabutyl orthotitanate(TBOT), and the SiO₂/TiO₂ bilayer coatings with antireflection property were obtained by dip-coating method. The performances of the coatings were analyzed with ultraviolet visible spectrophotometer (UV-Vis), X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), ellipsometer and contact angle measurement. The self-cleaning function of coatings was evaluated by means of photocatalytic degradation of methyl orange in aqueous solution, and scratch-resistant property of the coatings was studied. The results indicate that the peak transmission of the SiO₂/TiO₂ bilayer coating is up to 97.2% in the visible band, the coating has a flat surface, a dense structure and a low roughness. After illuminated by ultraviolet light for 2h, the SiO₂/TiO₂ bilayer coating is superhydrophilic with water contact angle up to 0°, and the 5mg/L methyl orange can be degraded by 43.6% in 2h. Moreover, the SiO₂/TiO₂ bilayer coating has an excellent scratch-resistant property.

A newly structured tandem dye-sensitized solar cell (tandem DSC) based on stainless mesh was introduced, in which the electrode constituted a first TiO₂ film on TCO and a second TiO₂ film on stainless mesh. Negative interaction between different dyes in this structure is less than that by normal method of cocktail-dyes dipping. The application of stainless mesh here reduces the loss of incident light, solves the problem of electronic connection between two different TiO₂ films, as well as improves electron transport and collection. This tandem cell achieved a power conversion efficiency of 1.96% with short circuit current density of 8.4mA/cm². Compared with normal mono-layer DSC with similar cell thickness, efficiency was improved about 62% by this tandem structure. Electrochemical impedance spectroscope (EIS) was used to analyze the electron transport in tandem DSC, and an equivalent circuit for tandem DSC was also proposed here. Meanwhile, the increased cell thickness and electron recombination on the surface of the stainless mesh have obvious influence on the photovoltaic performance.

The amorphous bulk Si-C-N ceramic was prepared by chemical vapor deposition (CVD). The thermal behaviors of as-prepared Si-C-N ceramic were investigated using TG/DSC, XRD, SEM and TEM. The phase separation firstly occurred in amorphous Si-C-N during the heat treatment, and one of separating phases appeared granular. β-SiC was formed in the granular separating phase. The amorphous Si-C-N began to crystallize at about 1200℃ when the ceramic exposed to the heat treatment. The crystallization temperature was about 1372.6℃, which was determined by DSC under the condition of continuous heating at a heating rate of 20℃/min. β-SiC was found at 1200℃, while β-Si₃N₄ and α-SiC were formed at about 1500℃. A laminate-like structure appears in the heat-treated Si-C-N. This kind of structure was proved to be the highly crystallized Si-C-N.