Perovskite solar cells have recently achieved photo-electric conversion efficiency over 19% showing a promising future for a cost-competitive potovoltaic technology. However, the study of perovskite solar cells' stability didn't catch up with the step of efficiency's process, which is the key issue for commercial application of perovskite solar cells. This review discussed the basic issues of the perovskite solar cells' stability under different circumstances, such as oxygen and moisture, UV light, solution process (solvents, solutes, additives), and temperature etc. and summarized how to control the perovskite solar cells' stability under the conditions above. The purpose is to provide a better understanding about perovskite solar cells'stability and the methods to increase the stability of perovskite solar cells under different circumstances.

In recent years, remarkable achievements have been made in the field of the visible-light-induced photoredox catalysis. Many highly efficient and environment-friendly reactions have been developed and used in the construction of complex molecules. This manuscript will highlight the latest advances in this research area and overview the applications of this strategy as the key step in the total synthesis of natural products and natural product-like compounds.

Research into organic-inorganic metal halide perovskite solar cells has swiftly gained momentum since the seminal work initiated by Kojima et al. in 2009, and already has delivered impressive accredited power conversion efficiency of over 17.9% within 5 years. In much previously reported research, the I-V characteristics was found to vary to a great extent with sweeping direction, which is known as I-V hysteresis. Further investigations have identified that the I-V hysteresis is also related to scanning speed, starting voltage and light soaking. We correlate such a phenomenon to different device structures and several possible causes were analyzed herein. A reliable test to obtain valid power conversion efficiency, which is to hold the device under a maximum power voltage is recommended for future research regarding this newly emerged technology.

Heteropoly acid such as phosphotungstic acid or silicotungstic acid was photoreduced to heteropoly blue in glycerol aqueous solution. Sensitization of Pt/TiO₂ by the heteropoly blue was found to be active for hydrogen generation under visible light irradiation. The apparent quantum yield of 3.4% for the photocatalytic hydrogen generation has been achieved with glycerol as an electron donor under 650～700 nm visible light.

Porous materials have been intensively applied in fields of ion exchange, adsorption and separation, host-guest chemistry, etc. The development of porous materials has fundamental and practical significance. Based on the component and constructing bond of porous materials, they include zeolite, mesoporous materials, metal-organic frameworks (MOFs) also known as coordination polymers, and porous organic frameworks (POFs). Compared with other porous materials, POFs could be considered as a new star. POFs are constructed by the designable and tunable organic building units (OBUs) via robust covalent bonds. Therefore, POFs display a series of advantages, such as diverse skeletons, high stability, high surface area, tunable pore, etc. The synthesis procedure could be described as the assembly of building units via specific acting force. In this review, we will introduce the synthetic principles, gas storage, catalysis, and other applications of the advanced POFs.

Amorphous hydrous nanostructured MnO₂ was synthesized in chemical coprecipitation method by mixing KMnO₄ and manganese acetate aqueous solution using polyethylene glycol(PEG) as disperser.The product was characterized by SEM, TEM, FT-IR, XRD and BET.The results show that the amorphous hydrous nanoparticles with the mean particle size of 10～30 nm were obtained and BET specific surface areas are 160.7 m²/g.Electrochemical characterization was carried out by cyclic voltammetry (CV).Amorphous α-MnO₂·nH₂O in 1 mol/L Na₂SO₄ aqueous electrolyte was proved to be an excellent electrode material for supercapacitor.The specific capacitance of 203.4 F/g was obtained at the scan rate of 4 mV/s in the range of -0.2～0.9 V (vs.SCE).

Over the past years, two-dimensional (2D) nanomaterials especially transition metal dichalcogenides (TMDs) have emerged as promising semiconductor materials to complement graphene-based electronics. They grain lots of attention due to their large number of candidates and varieties of physical properties. In this family, there are a wide range of materials exists ranging from Mott insulator semiconductor, metal, even to superconductor. Some of them, e.g. MoS₂, MoSe₂, WS₂ and WSe₂ have been widely investigated in these years, and they show unique properties for artificial van der Waals solids, electronics with ultra-low energy consumption, valleytronics, non-linear optics and high performance catalyst for hydrogen evolution reaction, while many of them still await a thorough theoretical and experimental exploration. Scientists in this field have try their best to modify the properties of this unique family. Charge carrier control is a key issue in the development of electronic functions of semiconductive materials. Beyond the simple enhancement of conductivity, high charge carrier accumulation can realize various phenomena, such as chemical reaction, phase transition, magnetic ordering, and superconductivity. In 2007, Hebard et al. reported the first electric-double-layer transistors (EDLT) using ionic liquid as the gate dielectric, the mobility was increased by 3 cm²·V^－1·s^－1 than the traditional transistor, this was the first demonstration that EDLT can be used to enhance the performance such as the mobility and the operation voltage of the devices. After that work, many works have been done using EDLT method. Very recently, scientists found that EDLT is also applicable for modifying the electronic properties of both organic and inorganic materials by control the charge carriers in the interface of the EDLT. Based on this method, high transistor performance, insulator-metal transitions, superconductivity, and even ferromagnetism have been released. In this review, we introduce and review the recent work for modifying the electronic properties based on 2D TMD materials.

The electronic structures and the optical response functions of In2O3 are were calculated by using a first-principles ultra-soft pseudo-potential approach of the plane wave based upon the density functional theory(DFT), and the relationships between the electronic structures and optical properties are were investigated. The dielectric functions, reflectance spectra, energy-loss function Im dominated by electron inter-band transitions are were analyzed in terms of the precisely calculated band structure and density of state. The properties of chemistry and physics are were studied by the difference charge density. The calculated results indicate that the optical transmittance of In2O3 is higher than 85% in the visible region, and can prepare transparent conductive Ooxide thin films can be prepared. Furthermore, the calculated conclusions offer theory theoretical data for the design and application of optoelectronics materials of In2O3, and also enable more precise monitoring and controlling during the growth of In2O3 materials as to be possible.

Organic-Inorganic hybrid solar cells combine the advantages of organic and inorganic semiconductors, and possess promising application prospect. Although the active layer in hybrid solar cells is the most important, the electrode buffer layers, including cathode buffer layer and anode buffer layer, have a great influence on the power conversion efficiency (PCE) of the cells. Inorganic semiconductors are often used as the electrode buffer layers because of their high chemical stability, high carrier mobility, and high transparency. TiO₂ and ZnO are the most widely used inorganic electron transport layer materials while inorganic hole transport layer materials, such as CuI, CuSCN and NiO, have been applied frequently in organic-inorganic hybrid solar cells. Here, we briefly review the progress on inorganic buffer layer materials in hybrid solar cells.

Graphene and carbon nanotubes are nanometer-sized carbon materials with the characteristics of the great specific surface area, good electrical conductivity and excellent mechanical properties. Selecting appropriate methods to prepare graphene/carbon nanotube composites can generate a synergistic effect between them with many physical and chemical properties enhanced, and these composites have a great future in many areas. In this paper, some kinds of preparation methods about graphene/carbon nanotube composites were described in detail, such as chemical vapor deposition, layer by layer deposition, electrophoretic deposition, vacuum filtration, coating membrane and in situ chemical reduction method. The advantages and disadvantages of these methods were compared as table format. To further enhance the functions, the graphene/carbon nanotube composites were doped with other materials such as polymer materials, nanoparticles, metal oxide to achieve the purpose of modification. Some researchers proposed theoretical computer model design for some special composites structures such as three-dimensional columnar structure and spiral structure to improve the performance of composites. Meanwhile, the applications of composites in supercapacitor, a photoelectric conversion device, energy storage batteries, electrochemical sensors and other fields were discussed in detail. These applications fully proved that composites had a brighter future than pure graphene or carbon nanotube. In addition, the developments of composites are prospected. Preparations of grapheme/carbon nanotube composites are maturing, but a variety of methods have their drawbacks and shortcomings, to get preparation method with easy control operation, low production costs, high raw material utilization, good product quality needs further research and exploration. Preparations of the highly oriented columnar structures between the layers of graphene and carbon nanotube and three-dimensional structure with graphene helicaly inserted or wrapped carbon nanotubes still remain in the computer model. In the near future the studies of the composites will be deepen and extended to develop new fields.

The influence of temperature on the electron property of anodic corrosion film formed on lead in a 4.5 mol/L H₂SO₄ solution, was investigated by using linear sweep voltammetry, A.C. voltammetry, electrochemical impedance spectroscopy (EIS) and Mott-Schottky plot methods. The results showed that the film resistance and film porosity increased, but the transfer resistance decreased with increasing the solution temperature. The EIS results implied that the film growth was controlled by a solid-phase mechanism and the Mott-Schottky curve revealed that the film exhibited an n-type semiconductive character, and the donor density decreased with the increment of the solution temperature.

Aqueous sodium-ion batteries recently have been widely and deeply studied in the energy field due to their prominent advantages such as high safety, low cost and environmental friendliness. Remarkable progresses of aqueous sodium-ion batteries gradually encourage their process of industrialization. However, compared with the organic secondary ion batteries, the development of aqueous sodium-ion batteries is limited by the narrow stable voltage window of the electrolyte and the poor cycle stability of the electrode material. How to solve these problems is still the key to the development of aqueous sodium-ion batteries. The latest developments in electrode materials, electrolyte and current collector of aqueous sodium-ion batteries, as well as challenges and possible solutions for developing high-performance aqueous sodium-ion batteries are mainly summarized in this review. Furthermore, the development prospects of aqueous sodium-ion batteries are discussed.

Aqueous zinc ion batteries (AZIBs) as an emerging battery energy storage technology have attracted widespread attention and developed rapidly in recent years due to the merits of high safety, low price, high energy density, environmental friendliness, easy manufacturing, etc., showing good application value and prospect in large-scale energy storage and other fields. Embarking from the current scientific issues existed in AZIBs, we review the important progress in cathode and anode materials and electrolyte used in AZIBs in this article. Firstly, the characteristics of multiple cathode materials that developed and their electrochemical reaction mechanism are analyzed and summarized. Afterward, the challenge and improving strategy for metal zinc anode are discussed, and the features of different aqueous electrolytes and the optimization solution are analyzed. Finally, the scientific problems to solve and technical challenges for the practical application in the future of this novel battery technology are summarized and prospected.

Graphene, a monolayer of carbon atoms packed into a two-dimensional crystal structure, attracted intense attention owing to its unique structure and optical, electronic properties. Raman spectroscopy is a quick and precise method in material science and has been employed for many years to investigate material properties. It can be used to investigate the electronic band structure, the phonon energy dispersion and the electron-phonon interaction in graphene systems. In probing graphene's properties, Raman spectroscopy is considered to be a reliable method. In this review, we highlight recent progress of studying graphene structure using Raman spectroscopy. First, on the basis of systematically analyzing the phonon dispersion of graphene, the typical Raman scattering features of graphene, such as G band, G' band, and D band, and the basic physical process are introduced. Using these Raman fingerprints, we can quickly and directly distinguish the layer thickness of graphene, determine the edge chirality and monitor the type and density of defects in graphene. Second, stacking disorder will significantly modify the optical properties and interlayer coupling stretch of few-layer graphene so that the Raman features of graphene will be strongly influenced not only in the G band intensity but also in the intensity, lineshape and the frequency of G' band. According to the peak position, width, and intensity of the Raman G band and G' band in graphene, we also discuss the influence of doping, substrate, temperature, and strain on the electronic structure of graphene. Finally, we introduce the second order overtone and combination Raman modes and the low frequency Raman feature (shear and layer breathing mode) in graphene, and discuss the dependence of these peaks on the structure of graphene.

With the development of intelligent terminals, wearable electronic devices show a great market prospect. As one core component of the wearable electronic device, the sensor will exert a significant influence on the design and function of the wearable electronic device in the future. Compared with the traditional electrical sensors, flexible wearable sensors have the advantages of being light, thin, portable, highly integrated and electrically excellent. It has become one of the most popular electronic sensors. This review focused on recent research advances of flexible wearable sensors, including signal transduction mechanisms, general materials, manufacture processes and recent applications. Piezoresistivity, capacitance and piezoelectricity are three traditional signal transduction mechanism. For accessing the dynamic pressure in real time and developing stretchable energy harvesting devices, sensors based on the mechanoluminescent mechanism and triboelectric mechanism are promising. Common materials used in flexible wearable electronic sensors, such as flexible substrates, metals, inorganic semiconductors, organics and carbons, are also introduced. In addition to the continuously mapping function, wearable sensors also have the practical and potential applications, which focused on the temperature and pulse detection, the facial expression recognition and the motion monitoring. Finally, the challenges and future development of flexible wearable sensors are presented.

The present paper describes the protocol for the preparation of a home made chiral micro-HPLC system and the chiral packing material with cellulose-based chiral stationary phase. The column packing technique was investigated and the key factors which may influence the performance of the chiral separation system were evaluated with several chiral compounds. The composition of the mobile phase and its flow rate were optimized. Finally, five enantiomers were successfully separated. It was illustrated that the system was characterized by simplicity, high resolution, low consumption of the mobile phase and high speed. The system cauld be easily prepared at the laboratory for enantioseparation.

Lithium-ion battery has developed rapidly in the past decades due to growing needs of electronic and information industries. Nowadays, the demand for lithium-ion batteries is still increasing and safety requirements are higher and higher. Therefore, exploration of a new anode material that is high safety and excellent cycle ability, as compared to commercial carbon/graphite materials, has been extensively attempted to meet the new need such as electric vehicles industry. Spinel Li₄Ti₅O₁₂ as an anode material of power lithium-ion battery has become a research hotspot due to its appealing features such as "zero-strain" structure characteristic, excellent cycle stability, low cost, simple synthesis, high safety feature and flat charge-discharge voltage plateau (1.55 V vs. Li/Li⁺). It is also considered as one of the most promising anode material for lithium-ion battery. Despite many advantages associated with Li₄Ti₅O₁₂, it can not meet the need of large-scale applications due to its pretty low electric conductivity (10^-13 S·cm^-1), moderate Li⁺ diffusion coefficient (10^-9～10^-13 cm²·s^-1) and theoretical capacity (175 mAh·g^-1). Several methods have been utilized to improve the conductivity and energy density of Li₄Ti₅O₁₂, such as synthesis of nano-sized particle, ion doping, doping Li₄Ti₅O₁₂ with other metals or metal oxides, coating Li₄Ti₅O₁₂ with conductive carbons, nitridation on Li₄Ti₅O₁₂ surface and composite anode materials prepared by Li₄Ti₅O₁₂ and other anodes. In addition, unique structure has been proved as an effective way to improve the electric conductivity of the material. Moreover, morphology has also an important effect on electrochemical performances of Li₄Ti₅O₁₂ such as specific capacity, specific energy, specific power, high rate performance and cycle life. This review focuses on the present status of different morphologies Li₄Ti₅O₁₂ including spherical structure, porous (hollow) structure, nano-micro structure, core-shell structure, one-dimensional, two-dimensional and three-dimensional nanostructures, then summarized their advantages, resolved and unresolved problems, common synthesis methods and application areas, respectively. At last, the future development prospects of Li₄Ti₅O₁₂ are presented.

The concept of the molecular orbital composition is often involved in quantum chemistry literatures. However, no enough emphasis has been placed on the corresponding calculation methods, and even there exist some serious misunderstandings. In this article, the basic concepts and calculation methods of composition of basis functions, atomic orbitals and atoms in molecular orbitals are discussed in detail, the differences between various methods are analyzed and compared with examples, meanwhile, the problems in calculations and analyses that need to be noticed are pointed out, the suggestions for choosing appropriate calculation methods are also given.

All-solid-state lithium ion battery has become an important focus due to higher safety, higher energy density and wider operating temperature compared to the commercial lithium ion battery with liquid organic electrolyte. Research and development of solid electrolyte are the keys for the successful market penetration of all-solid-state lithium ion battery. Nowadays, three kinds of solid electrolytes, polyethylene-oxide (PEO) as well as its derivatives based polymer electrolyte, LiPON thin film electrolyte, and glassy sulfide electrolyte, are widely studied and open very interesting new application prospects of all-solid-state lithium ion battery. Three major parameters of ionic conductivity, compatibility with electrodes, and manufacturing costs are used to evaluate the application prospects of the electrolyte. Based on that, PEO and its derivatives have low fabricating cost and good compatibility with electrodes. However, because of low lithium ionic conductivity at ambient temperature, the batteries using this electrolyte needs to work at high temperatures with a temperature control system. LiPON is most suitable for ultra-thin-battery and micro-battery, which present long cycle life and good rate performance. But, it is difficult for large-scale production of the batteries due to high cost and complex manufacturing processes. Glassy sulfide electrolyte exhibits the highest lithium ion conductivity (10^-3～10^-2 S/cm at 25 ℃) among the three electrolytes, which is close to the level of liquid organic electrolyte and meet the requirement in industrial application. However, advanced manufacturing technologies of the battery are required for the improvement of contacts at electrolyte/electrodes interface. In recent years, all-solid-state battery samples and pilot production lines are available on the market. In this review, we summarize the research progresses and production technologies of batteries based on the three solid electrolytes, and attempt to explore the commercial applications of all-solid-state lithium ion battery.

Hydrogen-bonded organic frameworks (HOFs), usually self-assembled by organic or metal-organic building blocks via intermolecular H-bonding interactions, have become a unique type of crystalline porous material. Although the weak and flexible nature of hydrogen bonds makes most HOFs fragile, the high stability and permanent porosity could be realized by the judicious selection of rigid building blocks with special spatial configuration as well as the introduction of framework interpenetration and/or other intermolecular interactions like π-π stacking and electrostatic interactions, etc. Compared with other crystalline porous materials like metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs), HOFs feature mild preparation condition, high crystallinity, permissible solution processability, easy healing and regeneration, etc. These distinguishing merits make HOFs capable to be used as unique multifunctional porous materials. Herein, we first review the basic rules to design and synthesize stable and porous HOFs, and then systematically summarize the representative supramolecular synthons and backbones that have been used to build stable and porous HOFs. Emphasis is put on the potential applications of HOFs in gas adsorption and separation, proton conduction, heterogeneous catalysis, luminescence and sensing, biological applications, enantiomeric resolution and aromatic compounds separation, pollutants removal, and structure determination, etc.

An effective method denoted as “center of mass probability distributions” was employed to study the methane adsorption mechanism in metal-organic framework PCN-14 which shows the highest methane storage capacity to date, finding that this material has two adsorption sites for methane molecules, and the organic linkers play an important role in adsorption. Thus, a new material named PCN-M was designed by modifying the organic linkers of PCN-14. The newly designed MOF material has a methane storage capacity of ca. 257 V/V at 290 K and 3.5 MPa, which is 12% higher than that of PCN-14. On the other hand, it has a methane capacity of ca. 241 V/V at 298 K and 3.5 MPa, which is 34% over the DOE target (180 V/V). In addition, this work shows that a rational modification of the organic linkers is a feasible way to improve the methane storage capacity, providing helpful information for future MOF design.

Emerging as a relatively new class of porous materials, metal-organic frameworks (MOFs), possessing diversified, designable and tailorable structures as well as ultrahigh surface area, have captured broad research interest and shown potential applications in many fields in recent years. In particular, MOFs have attracted intensive attention in catalysis. In the first two parts of this review, according to the origin of active sites, for examples, coordinatively unsaturated metal centers, functional organic linkers, functional sites chemically grafted onto the framework, as well as metal complexes or metal nanoparticles (MNPs) encapsulated inside the MOFs, etc., we have summarized the recent progress in heterogeneous catalysis over MOFs and their composites in recent several years. In addition, the MOF-based photocatalysis and electrocatalysis have also been briefly introduced in the subsequent two parts. Finally, the further development and challenge in MOF catalysis are discussed.

Sodium ion battery was initially researched alongside lithium ion battery in the late 1970s and through the 1980s. For the benefits of lithium ion batteries, namely higher energy density as a result of higher potential and lower molecular mass, shifted the focus of the battery community away from sodium. While lithium-ion battery technology is quite mature, there remain questions regarding lithium ion battery safety, lifetime, poor low-temperature performance, and cost. Furthermore, the rising demand for Li would force us to consider the growing price of Li resources due to the relative low abundance and uneven distribution of Li. Therefore, to explore low cost, highly safe, and cycling stable rechargeable batteries based on abundant resources is an urgent task. Due to the huge availability of sodium, its low price and the similarity of both Li and Na insertion chemistries, sodium-based batteries have the potential for meeting large scale grid energy storage needs. In spite of the lower energy density and voltage of Na-ion based technologies, they can be focused on applications where the energy density requirement is less drastic, such as electrical grid storage. In the past couple of years, the sodium-ion battery field presented lots of sodium-ion technologies and electrode materials. These range from layered oxides materials to polyanion-based materials, carbons and other insertion materials for sodium-ion batteries, many of which hold promise for future sodium-based energy storage applications. Much work has to be done in the field of Na-ion in order to catch up with Li-ion technology. Cathodic and anodic materials must be optimized, and new electrolytes will be the key point for Na-ion success. This review will gather the up-to-date knowledge about Na-ion battery electrode materials and electrolyte, with the aim of providing a wide view of the system that has already been explored and a starting point for the new research on this battery technology.

Graphene and graphene oxide have attracted tremendous interest over the past decade due to their unique electronic, optical, mechanical, and chemical properties. Pristine graphene is desirable for applications that require a high electrical conductivity, while many other applications require modified or functionalized forms such as graphene oxide due to its good dispersibility in various solvents. Surface functional modification of graphene and graphene oxide is of crucial importance for their broad applications. Functionalization of graphene enables this material to be processed by solvent assisted techniques, such as layer-by-layer assembly, filtration. It also prevents the agglomeration of single layer graphene and maintains the inherent properties. Structurally modifying graphene and graphene oxide through chemical functionalization reveals the numerous possibilities for tuning its structure. Several chemical and physical functionalization methods have been explored to improve the stabilization and modification of graphene. This review focuses on the surface functional modification of graphene and graphene oxide. The preparation method, basic structure and properties of graphene and graphene oxide were briefly described firstly. On the one hand, in the light of bonding characteristic, the surface functionalization of graphene and graphene oxide is divided into non-covalent binding modification, covalent binding modification and elemental doping. On the other hand, non-covalent functionalization contains four categories: π-π stacking, hydrogen bonding, ionic bonding effect and electrostatic interaction. Meanwhile, covalently functionalization includes four categories: carbon skeleton modification, hydroxy modification, carboxy modification and epoxy group modification due to the reactive functional groups. Doping functionalization consists of N, B, P and other different elements. According to the classification of surface structure characteristics, selected typical case has described the functional modification process in detail. The properties and application prospects of the modified products are also summarized. Finally, current challenges and future research directions are also presented in terms of surface functional modification for graphene and graphene oxide.

Over the past few years, the external quantum efficiency (EQE) of organic-inorganic hybrid perovskite light-emitting diodes (LEDs) has experienced a tremendous progress. The reported highest EQE of infrared and green perovskite LEDs has reached 21.6% and 20.3%, respectively, which is comparable to commercial organic light-emitting diodes. Even the slightly inferior blue perovskite LEDs have a recorded EQE of 12.3%. However, poor device stability is the biggest problem hindering the commercial application of perovskite optoelectronic devices, which is a severer problem in LEDs because the higher operating voltage will trigger acute ion migration. Encouragingly, however, the lifetime of perovskite LEDs has increased from the initial several seconds to over 200 hours, presenting a dramatic progress. The outstanding performance of perovskite LEDs is closely related with the excellent material properties, including tunable bandgaps, narrow full width at half maximum (FWHM), high defect tolerance, high electron/hole mobility and solution processibility. Moreover, the diversity of components and structure of perovskite makes the addition of various additives effective, enabling optimizing device performance through kinds of chemical methods. In this review, we analyzed the impacts of component and structure designing on the efficiency and stability of perovskite LEDs from the perspective of compositional designing, defect passivation and interfacial modification. We analyzed how compositional designing affects the optoelectronic properties through altering the ratio between organic and inorganic components or adding other molecules and ions to adjust the dimension of perovskites. As for defect passivation, we discussed various passivating reagents and their working mechanism. In addition, we summarized the significance of interfacial modification between different functional layers, including improving the wetting property of the substrates, achieving higher crystal quality of perovskite films, passivating the defects at the interfaces, blocking leakage current and reducing hole/electron injecting barrier. Finally, we discussed the scientific and technological challenges yet to be resolved before perovskite LEDs can be considered for commercial applications.

Fe3O4 magnetic nanocrystals were prepared by coprecipitating Fe2＋ and Fe3＋ ions in an ammonia solution with ultrasonic enhancement and modification by the anionic surfactant sodium dodecyl sulfate (SDS). The product was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), high resolution transmission electron microscopy (HRTEM), N2 absorption-desorption, and thermogravimetric-differential scanning calorimetry (TG-DSC), respectively. The surface electrical properties and magnetic properties of the Fe3O4 magnetic nanocrystals were systematically investigated. The growth mechanism of the Fe3O4 magnetic nanocrystals was discussed. The results show that the Fe3O4 magnetic nanoparticles obtained are well-crystallized particles, with an average size of 10 nm, which have good dispersivity. The specific surface area of particles can reach as much as 91.6 m2•g－1. The obtained nanoparticles also have good thermostability, and the isoelectric point (IEP) under water conditions is at pHpzc＝5.7. Magnetic measurement reveals the magnetic nanoparticles are superparamagnetic with a saturation magnetization of 65.0 emu•g－1. The ultrasonic enhancement and the surfactant modification play an important role in the growth mechanism of the Fe3O4 superparamagnetic nanocrystals. These superparamagnetic nanocrystals might be applied to biological and medical fields such as cell or enzyme immobilization.

The electrochemical performances of S₈ and polyanthra [1 ,9 ,8 -b,c,d,e][4 ,10 ,5 -b ,c ,d , e ]bis-[1,6,6a(6a-S^IV)trithia]pentalene (PABTH) in PEO-based polymer electrolyte are studied. It s found that there are phenomena of the solution of reduction products in the discharging process for Li/PEO-based polymer electrolyte/S₈ cell and Li/PEO-based polymer electrolyte/PABTH cell. It suggests that ether-based electrolytes even in the form of polymer (such as PEO-based Polymer Electrolytes) can t alleviate the loss of active material in sulfur electrode for the dissolution of its reduction products. For alleviating the solution of reduction production, designing electrolyte solvent with a special structure is necessary. Moreover, preliminary investigation on discharge capacity of the Li/PEO-based polymer electrolyte/S₈ cell and PABTH/ PEO₂₀LiTFSI/Li cell show that the utilization of the active material is lower than that in liquid electrolyte. It due to that sulfur and PABTH isn t ionic conductor, and the diffusivity values of Li^＋ in sulfur and PABTH are very low. PEO molecular with a large volume can t penetrate into particle of sulfur and PABTH carrying Li^＋, this is another main reason. From this point of view, electrolyte solvent with a small volume is favorable to the utilization of sulfur and PABTH.

Identification of acetylated proteins was performed via identifying BSA-ac by two kinds of mass spectrometers including ESI-MS and MALDI-MS. The lysine-acetylated proteins can be confirmed from the observation of a specific ion at m/z 126.1 or a mass difference of 170 Da between the adjacent b-ions or y-ions. The LTQ-Orbitrap hybrid spectrometer (ESI-MS) comprising an LC pre-concentration system and an ESI ionization source could acquire much more information than the others. However, the ion at m/z 126.1 could not be detected with a linear ion trap analyzer, which was well observed through a 4700 Proteomic analyzer (MALDI-TOF-TOF). This diagnostic ion can also reduce the false positive rate. It has been demonstrated that ESI and MALDI MS are complementary to each other in analyzing acetylated proteins. Accordingly, it can be concluded from the fact that different results would be obtained with different mass spectrometers, and matched protocols should be used for the identification of the acetylated proteins.

Bases, either organic bases or inorganic ones, are very often added in transition-metal catalyzed organic reactions to promote the catalytic reaction efficiency and increase the yields of products. As a common practice for most published papers, a reaction condition screening table is given, listing a number of bases and the respective yield of products. However, no discussion or a little in some cases is provided on why one base works well to give a high yield formation of the product, but other bases afford no or low yields of the product. Furthermore, in many cases a certain base works well for one reaction but may not work for another. Indeed, for a complicated reaction mixture containing several different components, it is very difficult to analyze and understand the roles of certain bases. Yet there are sporadic discussions and rationalization on the roles of bases in the literature. The role of bases has been reported to be straightforward in some cases, for examples, to abstract protons or to neutralize acids in the reaction system, but very complicated in many other cases. The roles of bases may be affected by several factors, including basicity, solubility, ionization ability, solvent, aggregation state, the size of the metal cations, Lewis acidity of the metal cations, the HSAB theory, the size of the counter anions; the coordination ability of the counter anions, etc. In addition to abstract protons or to neutralize acids in the reaction system, a base may activate the catalysts and facilitate the regeneration of reactive catalytic species. The roles of the metal cation in a base may mainly influence the solubility of the base in organic solvents, or interact with substrates or solvents. The roles of the counter anion in a base may mainly contribute to the coordination with a metal center and subsequent stabilize the complex. The major differences between inorganic bases and organic bases include their solubility and bulkiness. Metal contaminants in bases may also have innegligible effect on the reactions, since in many cases a large excess amount of bases are added. This review is written based on the limited knowledge, focusing on commonly used inorganic bases such as LiOBu-t, NaOBu-t, KOBu-t, LiOAc, NaOAc, KOAc, LiOH, NaOH, KOH, Li₂CO₃, Na₂CO₃, K₂CO₃, Cs₂CO₃, KF, CsF and organic bases such as DBU and Et₃N.

Ternary layered oxides {Li[Ni_xCo_yM_z]O₂ (0 < x, y, z < 1, M=Mn, NMC; M=Al, NCA)} are one of the most promising cathode materials of lithium-ion batteries (LIBs). However, in the traditional electrolyte system, they will undergo dramatic structural changes and interface side reactions at high potential and high temperature, which will bring great challenges to their practical application, especially for their cycle life and safety. Developing appropriate electrolyte additive is one of the most economical and effective methods to improve the electrochemical performance of LIBs. Based on the intrinsic structure of material, electrolyte additives used for NMC and NCA ternary cathode and their reaction mechanism in the past 5 years are reviewed in this paper, which include vinylene carbonate (VC), fluoro-compounds, new lithium salts, P-based, B-based, S-based, nitrile, others and combinative additives. Among them, VC becomes a kind of universal additive, which can improve the efficiency and cycle life at low voltage and normal temperature. Fluoro-compounds have been developed from mono substituted such as Fluorinated ethylene carbonate (FEC) to multi-fluorine substituted, which can improve the stability of electrode/electrolyte interface under high voltage. New lithium salt additives are mainly used to improve the film forming performance under high voltage and high temperature, such as Lithium bis(fluorosulfonyl)imide (LiFSI), Lithium difluorophosphate (LiDFP). P-contained additives[such as Tris(trimethylsilyl) phosphite (TMSPi)] are mainly to improve the stability of anode-electrolyte interface, and it has obvious synergistic effect when they combined with additives such as VC. B-contained additives are mainly used to improve the dissociation degree and stability of lithium salt, such as Tris(trimethylsilyl)borate (TMSB). S-contained additives are mainly used to improve the ionic conductivity and stability of anode SEI film, such as Prop-1-ene-1,3-sultone (PES). Nitriles are benefited from the strong electron withdrawing effect of -CN, which can improve the stability of the electrode/electrolyte interface at high voltage. Other types of additives are some heterocyclic compounds having film forming ability and various silanes which can eliminate HF and H₂O. Combinative addi-tives are developed from VC based composite to PES and PBF (pyridine boron trifluoride) system, which can endure even harsher conditions.

Click chemistry has been widely applied to the functionalization of graphene due to its special properties of easy process, flexibility and high efficiency. In this paper, we have present a detailed review of the functionalization of graphene and graphene oxide via click chemistry. The functionalization methods through click chemistry can be divided into two main strategies of the covalent functionalization and the non-covalent functionalization. In addition, the former is further discussed in term of chemical bonds formed on the edge of graphene and chemical bonds formed on the surface of graphene via click chemistry. First, we provide a detailed classification and summary of the reaction process, condition and characterization of the functionalization through click chemistry. On the one hand, according to the position where the click chemistry takes place, the clicking functionalization of graphene can be classified into click reaction on the edge of the graphene oxide, click reaction on the surface of the graphene oxide, click reaction on the surface of the graphene, Diels-Alder[4+2] click reaction on the surface of the graphene, and click chemistry via π-π non-covalent functionalization. Moreover, we have presented and discussed significant research references related to the above five parts. On the other hand, the synthetic routes including the linking methods, click reaction conditions, reaction conditions of the alkynylation and azido functionalization of the graphene, graphene oxide, and the corresponding reactants have been summarized and listed. In addition, the functional properties and the potential applications of the functionalized graphene and graphene oxide are also concluded. To further clearly illustrate and make a summary of the functionalization method of graphene and graphene oxide via click chemistry in details, a table is listed and shown in the paper. Furthermore, we have elaborate the common characterizations methods including IR, Raman, UV, ¹H NMR, ¹³C NMR, XPS, XRD, AFM, TEM, SEM, CV, TGA, and the common characterization results are analyzed and briefly discussed. At last, the potential application of click chemistry on the functionalization of graphene and graphene oxide was summarized.

Transition metal catalyzed asymmetric reaction is a hot issue and a frontier of the research in current organic chemistry. The design and synthesis of new type of efficient chiral ligands and chiral catalysts, esspecially those with novel skeleton is the focus of research in asymmetric catalysis. Since 1990's, chiral ligands based on spiro skeletons have received increasing attention and gradually developed into a new type of chiral ligands with distinctive characteristics. The skeletons of the chiral spiro ligands developed from spiro[4.4]nonane with three chiral stereocenters to spirobiindane and spiro[4.4]nonadiene with only one axial chirality, as well as other types of spiro skeletons. Nowadays, the library of chiral spiro ligands contains a wide range of chiral spiro ligands with different skeletons, including chiral spiro monophosphorus ligands, diphosphine ligands, phosphine-nitrogen ligands, dinitrogen ligands, and etc. Many of these chiral spiro ligands and related catalysts not only have shown high catalytic activity and high enantioselectivity for various asymmetric reactions such as asymmetric hydrogenations, asymmetric carbon-carbon bond forming reactions, and asymmetric carbon-heteroatom bond forming reactions, but also have made the enantiocontrol of many catalytic asymmetric reactions, which are difficult in obtaining high enantioselectivities, more easily and possible. The chiral spiro skeleton has become a ‘privileged structure’, and chiral spiro ligands and catalysts have been used in the syntheses of different type of chiral compounds including chiral natural products and chiral drugs. The emergence of chiral spiro ligands increased the dynamism of research on finding new chiral ligands and catalysts, and promoted asymmetric synthesis chemistry. Henceforth, the focus of study in chiral spiro ligands will continue to be the development of new chiral spiro ligands and catalysts with high activity and high enantioselectivity. At the same time, the applications of chiral spiro ligands in the new catalytic asymmetric reactions, and in the asymmetric synthesis of bioactive chiral compounds, chiral natural products and chiral drugs will become a new focus of research.

Formaldehyde was degraded with photo-catalysis by nano-titanium dioxide (TiO2) and 2-methyl- 2-nitro-propane (MNP) was used as a spin trap (ST). The radical intermediates in the process of reaction were studied and a new spin adduct (ST-R) was obtained. The results of electron paramagnetic resonance (EPR) indicated that the intermediate of formaldehyde degradation in aqueous solution was &#8226;CH(OH)2. A new degradation mechanism was proposed.

Amides are widely used as stable synthetic intermediates in organic synthesis and medicinal chemistry. Versatile and chemoselective C—C bond forming methods for the direct transformation of amides are highly demanding. In this paper, we report the reductive cycloaddition of common secondary amides with the Danishefsky diene to produce 2-substituted 2,3-dihydro-4-pyridones. This one-pot procedure involves amide activation with triflic anhydride, partial reduction, and [4+2] cycloaddition. The synthetic utility of this step-econimical method was demonstrated by the short and protecting-group-free total syntheses of alkaloids (±)-lasubine I and (±)-myrtine.

Nanometer TiO₂ supported on silica gel (supported nanometer TiO₂) was prepared by Sol-Gel method. The product was characterized using XRD and SEM. The adsorption behavior of supported nanometer TiO₂ towards Cd^2＋, Cr^3＋, Cu^2＋and Mn^2＋ was investigated by ICP-AES. It was found that the adsorption percentages of the metal ions studied were more than 90% in pH 8.0～9.0, and 0.5 mol/L HNO₃ was sufficient for complete elution. The adsorption capacity of supported nanometer TiO₂ for Cd^2＋, Cr^3＋, Cu^2＋and Mn^2＋ was found to be 8.3, 13.1, 12.6 and 5.1 mg/g, respectively. A method using supported nanometer TiO₂ as adsorbent coupled with ICP-AES has been developed for the separation/preconcentration and determination of Cd^2＋, Cr^3＋, Cu^2＋and Mn^2＋in environmental sample.

Doping is the most feasible and convenient method to modulate the band structure of graphene from semimetal to p-type or n-type material. In recent years, the chemical vapor deposition methods have been well developed to grow graphene layer with high quality and large area. This paper briefly reviews the recent research progress on doping methods of CVD graphene, including the doping effects by metals, small molecules, chemical reactions and replacement of lattice atoms. The methods of bilayer graphene band regulation as well as the fabrication of graphene p-n junction are also introduced, and the future tendency and potential applications of doped graphene are proposed. For graphene, it is relatively easy to produce p-type doping via surface absorption, exposing pristine graphene in those molecules with electron withdrawing groups (H₂O, O₂, N₂, NO₂, PMMA et al.) will lead to evident p-type doping, and graphene of this kind of p-type doping can rapidly recover to its original state when doping molecules are removed. If boron source was introduced into the CVD growth process of graphene, substitutional p-doping that some carbon atoms in graphene hexagonal lattice are replaced by boron atoms can be formed. Compared to the p-type doping, stable n-type doping is not facile for graphene. It has been proved that some electron-donating molecules such as ammonia, potassium, phosphorus, hydrogen and poly(ethyleneimine) (PEI) can produce n-type doping in graphene through surface electron transfer, but these doping effects are unstable. By introducing nitrogen-containing precursors in growth approach, small part of lattice carbon atoms will be replaced by nitrogen atoms which can result in effectively n-doping effect. Combine the p-type and n-type doping method together, the p-n junction can be produced in mono- or bi-layer graphene, a series of novel functional devices like photothermoelectric devices have been constructed using these hetero-doped graphene p-n junctions.

A kind of micro-meso hierarchical porous carbon (HPC) was prepared by a combination of organic-organic self-assembly approach and post-activation approach, and also investigated as an electrode material in electrochemical capacitors. Pore structure analysis shows that micropores can be adjustably generated on the mesopore wall of mesoporous carbon (MC) by post activation at high temperature using KOH as an activating agent. As evidenced by electrochemical measurements, HPC shows superior capacitive behavior (exhibiting a high capacitance of up to 168.9 F/g even at a very high sweep rate of 100 mV/s) to hard-templated carbon reported in the literature. Of special interest is the fact that HPC has very excellent capacitance at high frequency of 1 Hz, reaching up to 180 F/g that is the highest value than any other electrode material reported in the literature. The excellent capacitive performance of HPC can be ascribed to its unique hierarchical porous structure that favors the fast diffusion of electrolyte ions in its pore structure.

LiFePO4 is being used as the cathode material for Li-ion batteries of electric vehicle (EV) because of low cost and high safety. In this work, a carbon-coated LiFePO4 was synthesized by a thermal decomposition method using Li3PO4, FePO4, Fe powder and ethanol as the raw materials. Experimental results showed that LiFePO4/C particles were evenly distributed with the sizes of 200 nm～1 μm, the surface of particles was coated by carbon, and the particles were linked together by carbon fibers. The first discharge capacity of sample reached 137 mAh•g－1 and the first columbic efficiency was over 95%. After 50 cycles, the discharge capacity still remained unchanged, which indicated the good cycle capability and reversibility. Our research lowered the cost of Li-ion batteries and provided a feasible application in Li-ion batteries for industrial production.