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In this paper, a new type of Al-Ga-In-Sn-Si alloy anode with high negative potential and high activation was successfully prepared by modifying low melting point alloy elements such as Ga, In and Sn. The corrosion behavior and electrochemical performance of Al-Ga-In-Sn-Si alloy were studied through material characterization and electrochemical tests. A seawater dissolved oxygen battery was constructed with carbon fiber brush-graphene-platinum (Pt-G@CFB) catalytic cathode. The long period discharge performance of the battery under different constant resistance in indoor static and real dynamic seawater environment was investigated. The electrochemical test results of aluminum anode show that the self-corrosion potential of Al-Ga-In-Sn-Si alloy is −1. 613 V(vs. Ag/AgCl), and the self-corrosion current density is 1. 431 mA/cm² . The battery discharge test results show that the battery voltage rises with the increase of load resistance. The average discharge voltages of the dissolved oxygen battery in seawater are the highest, which are 1. 73 and 1. 78 V respectively, under the load of 2000 Ω in indoor static and real dynamic seawater, and the average energy densities are the highest under the load of 1000 Ω. They are 549. 85 and 653. 44 Wh/kg, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the complex Eu (HFA)4TPP (HFA=Hexafluoroacetylacetone, TPP= tetraphenylphosphonium) with high photoluminescence quantum yield and improved stability is prepared. The steric effect on luminescence performance is revealed by studying the crystal structures and luminescence properties of Eu(HFA)4Na and Eu(HFA)4TPP complexes. On this basis, the luminescent films are obtained by incorporating Eu(HFA)4TPP complex with high loading content into polymethyl methacrylate (PMMA) matrix, which shows a visible-light excitation window (240~450 nm) and high photoluminescence quantum yield of 60. 54%. In addition, the luminescent solar concentrators (LSC) in Eu(HFA)4TPP/PMMA film conformation is prepared. The optical conversion efficiency contribution of Eu(HFA)4TPP/PMMA film to the LSC is 0. 95% in the case of the G=1. 87, holding promise in photovoltaic fields. [ABSTRACT FROM AUTHOR]

The search for alternatives to fossil fuels has received a great deal of attention based on the urgency of reducing CO2 levels in the atmosphere and the demand for energy at this stage. Solar energy is the world's most abundant renewable energy source, and photocatalysis is a sunlight-driven chemical reaction process carried out on the surface of the photocatalyst. The realization of the carbon cycle is an urgent need for the development of human society. Photocatalysis has the advantages of low energy consumption and mild reaction conditions, and realizing the resource utilization of CO2 by simulating natural photosynthesis, which is one of the most promising means to solve this problem, and is of great significance for realizing carbon neutrality. The central issue in the case is the development of efficient, environmentally friendly and inexpensive catalysts. Titanium dioxide (TiO2 ) is favored in photocatalysis because of its high catalytic activity and excellent chemical stability. However, some bottlenecks still restrict the photocatalytic activity. Various methods have been tried to optimize the photocatalytic performance. This article summarizes the photocatalytic CO2 reduction based on TiO2 photocatalysts in recent years, which helps to comprehensively understand and grasp the research progress and trends in this field. This paper mainly discusses the mechanism of photocatalytic CO2 reduction, reaction system, and the research progress of TiO2-based catalysts in photocatalytic CO2 reduction. The active sites of TiO2-based photocatalysts are elaborated, focusing on the applications of titanium-oxo clusters, the construction of Lewis acid-base pairs, the establishment of heterojunctions, and the modulation of surface wettability. These strategies can not only increase the effective active sites on the catalyst surface, but also effectively enhance the separation efficiency of electron-hole pairs, so as to improve the photocatalytic CO2 reduction performance. Finally, the future opportunities and challenges in this field are prospected. [ABSTRACT FROM AUTHOR]

The safety issue of animal food has received widespread public attention due to increased reports of problematic foods. Once veterinary drugs are overused or abused in the process of animal husbandry, drug residues will bring serious harm to human health. Common residue detection methods have the disadvantages of high cost, slow speed and low efficiency, which usually requires professional personnel to operate, and the traditional physical and chemical methods can't meet the needs of food quality testing. As a result, the research and development of rapid and efficient detection methods for veterinary drug residues is necessary. In recent years, surface-enhanced Raman spectroscopy (SERS) has been widely used in many fields such as authenticity identification, illegal additives detection, agricultural and veterinary residues, etc, and has a broader development prospect in the field of food testing due to its advantages of fast detection and nondestructive. SERS is different from other detection methods in that it can rapidly identify target analytes through signal amplification and highly sensitive fingerprint spectroscopy for qualitative or semi-quantitative analysis. This paper mainly introduces the research and application of Raman spectroscopy and SERS in the detection of veterinary drug residues in foods of animal origin, focusing on the advantages of SERS, the pre-treatment of food samples, and the related research on the detection of a variety of veterinary drugs by SERS combined with other techniques, and proposing the challenges faced by SERS in practical monitoring. [ABSTRACT FROM AUTHOR]

The high performance liquid chromatographic (HPLC) fingerprints of TongFu XieXia Granules (TFXXG) are established, and the contents of Emodin, Chrysophanic acid, Rhein, Aloeemodin, Physcion, Magnolol and Honokiol are simultaneously determined. The separation is performed on a Waters Symmetry C18 column (2. 1 mm × 150 mm, 3. 5 µm) with a gradient elution of 0. 1% aqueous phosphoric acid (A) and methanol (B) as the mobile phases, at a flow rate of 0. 4 mL/min, with the column temperature at 30 ℃, the detection wavelength at 254 nm, and the injection volume of 10 µL. The fingerprints of 10 batches of TFXXG are established, and the similarity is calculated by using the “Evaluation system for similarity of chromatographic fingerprints of traditional Chinese medicines”(2012 version); the contents of Emodin, Chrysophanic acid, Rhein, Aloeemodin, Physcion, Magnolol and Honokiol are determined. The results show that a total of 25 common peaks is identified in the 10 batches of TFXXG, and the similarities are all above 0. 950; a total of 12 common peaks are identified, which are Sinapine thiocyanate, Caffeic acid, Echinacoside, Naringin, Neohesperidin, Aloeemodin, Rhein, Magnolol, Honokiol, Emodin, Chrysophanic acid and Physcion, respectively. The contents of Aloeemodin, Rhein, Magnolol, Honokiol, Emodin, Chrysophanic acid and Physcion are 0. 1244~0. 1304, 0. 4271~0. 4387, 3. 0479~3. 0853, 1. 2910~1. 3039, 0. 2427~0. 2523, 0. 7718~0. 7897 and 0. 5085~0. 5249 mg/g, respectively. The fingerprints and quantitative analytical methods constructed in this paper are reproducible and operable, and can be used to control the quality of TFXXG. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPs), as one of the most toxic pesticides, have the characteristics of wide use, large usage and great harm to human health. With people's longing and continuous pursuit of a healthy life, it is particularly urgent and important to build accurate, sensitive, convenient and fast OPs residual analysis and detection sensor. Because of the unique optical, electrochemical and biological properties of nanomaterials, OPs detection sensors based on nanomaterials have the advantages of sensitivity, high efficiency and economy. In this paper, the domestic and foreign sensors for detecting OPs residues based on rare earth doped up conversion nanomaterials, metal nanomaterials, metal oxide nanomaterials, carbon nanomaterials and quantum dot nanomaterials from 2015 to 2023 are reviewed, providing ideas and basis for the subsequent development of nanomaterial-based OPs multi residue detection sensors. [ABSTRACT FROM AUTHOR]

It is of great significance to select appropriate supports to support Pt nanoparticles for the preparation of efficient phenol hydrogenation catalysts. In this paper, Pt nanoparticles confined into the inner wall of titanium oxide nanotubes were prepared by template assisted method of atomic layer deposition technology. The specific preparation method was to use carbon nanofibers as templates, successively depositing Pt nanoparticles and thick titanium oxide shell on the templates surface. Then, the templates were removed by high-temperature sintering, through which Pt nanoparticles confined into the inner wall of titanium oxide nanotubes can be obtained. The particle size of the Pt nanoparticles ranged from 2. 0 to 3. 2 nm at a sintering temperature of 500 ℃, with an average size of 2. 6 nm. Transmission electron microscopy results confirmed that Pt nanoparticles with highly uniform size were evenly dispersed and embedded into the inner wall of the hollow channel of titanium oxide nanotubes. The results of the catalytic performance of phenol hydrogenation show that the small-size Pt nanoparticles have the best phenol hydrogenation activity, with a Turnover Frequency (TOF) value of 482. 1 h−1 at a sintering temperature of 500 ℃ . In addition, compared with the conventional Pt nanoparticles with the same size supported on the outer wall of titanium oxide nanotubes, it is found that the confined catalyst shows better catalytic activity. Furthermore, due to the protective effect of titanium oxide nanotubes, it can effectively prevent the aggregation and falling off of Pt nanoparticles in the reaction process. After the reaction, the Pt content only decreased by 4. 52%, and there were no significant changes in the morphology observed, thus the confined catalyst showing excellent catalytic stability compared with the supported catalyst. [ABSTRACT FROM AUTHOR]

Amino acids, as the fundamental components of proteins, contain both acidic and basic groups (amino and carboxyl groups) in their molecular structure, and amino acid ionic liquids with amino acids as anions or cations can be conveniently formulated. Amino acid ionic liquids with the advantages of high solubility, low melting point, and high thermal stability. These liquids find applications as carbon precursors, solvents, catalysts, and adsorbents in various fields such as energy storage, biomass utilization, and carbon capture. This paper provides an overview of the research progress made in the utilization of amino acid ionic liquids in supercapacitor electrode materials, biomass conversion, and carbon dioxide separation and capture in the past seven years. Specifically, it focuses on the advancements in utilizing amino acid ionic liquids as precursors in supercapacitor carbon electrode materials. Furthermore, it highlights the potential applications and future development prospects of amino acid ionic liquids. [ABSTRACT FROM AUTHOR]

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) are expected to be the next-generation NIR light sources, with the advantages of small size, broad bandwidth, and easy tuning of emission peaks. The key for NIR pc-LEDs is to develop highly efficient broadband NIR phosphors that can be effectively excited by blue light. Cr3+ -activated NIR phosphors have been widely studied, and this paper reviews the development of Cr3+ -doped NIR phosphors peaked at 800~900 nm. Based on phosphates, pyroxenes, and other systems, the relationships between the structure and the emission peak and bandwidth are summarized. Furthermore, to enhance the NIR performance, strategies of synthesis technology optimization, components design, and co-doping sensitizers are discussed in detail. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) have attracted much attention due to their unique structure and properties, especially in terms of maximizing the utilization of atoms and improving the intrinsic catalytic activity. In recent years, SAC-based advanced oxidation processes (AOPs) have become a new field in the environmental field, and have been widely used in the removal of various refractory organic pollutants. In this paper, the synthesis and characterization methods of SACs are analyzed, and the catalytic performance of SACs in different Fenton-like catalytic reactions is emphasized. In addition, tests of the continuous flow of SACs fixed on membrane or columnar filters are presented to explore the potential of SACs for practical applications in Fenton-like reactions. Finally, we prospect the future rational SACs design and the exploration direction of the Fenton-like reaction mechanism, aiming to improve the application potential of Fenton-like reaction in practical wastewater. [ABSTRACT FROM AUTHOR]

In recent years, due to the development of nuclear power and other industries, the pollution of heavy metals and radionuclides in water cannot be ignored, and the demand for clean water has become an important issue of global concern. Molybdenum disulfide (MoS2 ) nanomaterials have attracted much attention in the fields of sterilization, hydrogen storage, water purification,etc. Membrane technology has become one of the options for the removal of heavy metals and radionuclides from water based on the advantages of simple operation and high efficiency. In this paper, the research progress of MoS2-based nanomaterials and membranes in removing heavy metals and radionuclides from water is summarized, focusing on MoS2 synthesis and modification methods, the main affect factors and mechanisms of heavy metals and radionuclides removal by MoS2, the preparation of MoS2-modified membranes, and the research progress on removing heavy metals and radionuclides from water by membrane technology, which aims at efficiently removing heavy metals and radionuclides. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI), an emerging method for water desalination and ion separation, has received much attention due to its advantages of high ion selectivity, high water recovery and low energy consumption. Compared with the traditional carbon electrodes, the emerging Faraday electrode offers a unique opportunity to make the desalination performance of CDI significantly improved through the Faraday reaction of ion capture. Transition metal-based electrodes have received much attention in the field of CDI electrode design due to their highly reversible Faraday response, relatively high conductivity, and excellent theoretical pseudocapacitance values. In this paper, we systematically summarize and sort out the material classification of transition metal-based electrodes in CDI applications, and summarize the modification engineering performed for their intrinsic defects, mainly including conductive material coupling, functional architecture engineering and defect engineering, etc., and summarize their performance in CDI applications; in addition, the specific applications of transition metal-based electrodes in CDI are particularly introduced in terms of ion selective separation, metal ion removal and nutrient element recovery. Finally, the paper also outlines the remaining challenges and research directions to provide guidance for future development and research of transition metal chemical substance electrodes. [ABSTRACT FROM AUTHOR]

Aquaporins (AQPs) are membrane proteins that mediate the transport of water molecules with high selectivity and permeability to water molecules. Artificial water channels are generally assembled from various organic or inorganic materials (such as carbon materials, organic compounds, and peptides) and designed to mimic the structure and function of natural aquaporins. This paper describes the types, structures and their permeation mechanisms of natural, bio-inspired and synthetic water channels, and reviews and compares the research progress of artificial water channels such as single molecules, supramolecules and carbon nanomaterials over the last two decades. This paper elaborates on the influence of different artificial water channel material properties on the structure and function, and focuses on the shortcomings of artificial water channels and the challenges of developing new artificial water channels, and finally looks into the future prospects of artificial water channels. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) material, as a new multifunctional material, has attracted more and more attention in the field of water treatment of catalytic activation in advanced oxidation technology, due to its high surface area, adjustable pore structure, excellent thermal and chemical stability. This paper focuses on the research progress of activating persulfate by MOFs-based catalyst in the field of water treatment in recent five years. In this paper, various MOFs-based catalyst and their common synthesis methods in persulfate activation are introduced. Then, the oxidation mechanisms of MOFs-based catalyst during the activation of persulfate are summarized; the common modification methods of MOFs-based catalyst are introduced. Finally, some suggestions for the future research direction of activated persulfate by MOFs-based catalyst are put forward. This review will help to deepen the understanding of MOFs-based catalyst activating persulfate to degrade organic pollutants, and provide theoretical reference for the development of new heterogeneous MOFsbased catalysts based on PS activation. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) is the marker for early diagnosis of cancer and plays a key role in physiological and pathological processes, therefore real-time and accurate monitoring of miRNA is of great significance. Currently, signal amplification/magnification strategies for miRNA assay are mostly dependent on the involvement of coenzymes. In this paper, a highly sensitive and specific miRNA detection method based on gold nanoparticle (AuNPs) aggregation and hybridization chain reaction (HCR) enzyme-free amplification is established. An assisted hairpin probe (HP) and two universal hairpin probes (H1/H2) are designed. Both of them are single-stranded DNA (ssDNA) with sticky ends, which could stabilize AuNPs in aqueous solution and effectively prevent salt-induced aggregation. The target miRNA hybridizes with the HP loop region, initiating HCR to trigger the formation of double-stranded DNA (dsDNA) polymers. The dsDNA polymer has no sticky ends and no ability to stabilize gold nanoparticles, resulting in salt-induced aggregation of AuNPs, and the change of gold-colloidal solution from wine red to blue. Thus, miRNA can be detected by spectrophotometry. This strategy does not rely on enzymatic reactions, separation processes, and chemical modifications, and operation is simple. By designing the HP loop sequence, the detection of different targets can be realized and show good versatility. [ABSTRACT FROM AUTHOR]

Biomarkers, such as ions, small molecules, proteins, polysaccharides, nucleic acids, and cells, are involved in the building of organisms and play an important role in the life process. Accurate detection of these biomarkers is of great significance for disease research, early diagnosis, drug evaluation, and human health monitoring. The solid-state nanochannel is modified by functionalizing the outer surface of the nanochannel, which eliminates the restriction on the target molecule and greatly improves the speed and sensitivity of detection by means of a change based on the ion signal. This paper reviews the detection principle of solid-state nanochannels with modified outer surface in biomarkers, summarizes the research progress of solid-state nanochannels modified on outer surfaces in biomarker analysis, and briefly looks forward to the challenges and development opportunities of solid-state nanochannels modified on outer surfaces. [ABSTRACT FROM AUTHOR]

Recently, with the advance of agriculturalization, industrialization and urbanization, pollutants such as pesticides, veterinary drugs, heavy metal ions and dyes emitted from various industries have brought great harm to the ecological environment and human production and life. Therefore, it is important to adopt green and efficient methods to remove pollutants. Metal-organic framework （MOFs） is a kind of porous crystalline material composed of metal ions and organic ligands, which has the advantages of adjustable pore size and large specific surface area, and has a wide range of applications in various fields. However, while monometallic MOFs have excellent performance but small pores and few active sites, bimetallic MOFs formed by introducing a second metal ion have the advantages of abundant pores, large specific surface area, tunable structure and abundant active sites. Recently, they have been widely used in catalysis, storage, drug loading, and transportation. The increased adsorption sites and enhanced synergistic effects make the bimetallic organic frameworks materials potentially promising for applications in the field of adsorption. Therefore, this paper summarizes recent research progress on bimetallic MOFs, discusses the challenges that face in terms of synthesis and applications, and looks forward to their further development, providing references for the fabrication of bimetallic MOFs and applications in pollutant adsorption. [ABSTRACT FROM AUTHOR]

In recent years, with the research and development of liquid crystal microwave phase shifter technology, how to reduce the high frequency dielectric loss of liquid crystal materials has become a key issue in the development of microwave communication devices. In this paper, seven liquid crystal compounds (Ⅰ1−Ⅰ7) containing triphenylacetylene isothiocyanate with a wide nematic temperature range (89. 5~127. 7 ℃) were designed and synthesized, and Ⅰ1−Ⅰ3 had a relatively low melting point (45. 8~67. 2 ℃). These compounds are mixed with a solvent liquid crystal M composed of a variety of side ethyl triphenyldiacetylene liquid crystals in certain proportions, and their dielectric properties in the microwave frequency band (11~33 GHz) are tested by the rectangular resonant cavity perturbation method. The effects of the molecular structure and substituents on dielectric properties of liquid crystal at high frequency are investigated by molecular simulation. The experimental results show that the higher the dipole moment and polarizability, the higher the dielectric constant and higher frequency dielectric loss of the synthesized liquid crystal compounds；the introduction of branched chains in the terminal alkyl group not only reduces the melting point, but also decreases the dipole moment of the molecule, resulting in the decrease of the dielectric constant； the introduction of acetylene bond between benzene rings can increase the π -electron conjugation system and dielectric constant of the molecule, which can reduce the dielectric loss at high frequency； The dielectric anisotropy (Δεr ＞1. 025) of the isothiocyano-linked (—NCS) phenyl ring (X1 and X2 ) compounds is greater than that of the central phenyl ring (X3 and X4 ) compounds, but the dielectric loss of the latter is lower. [ABSTRACT FROM AUTHOR]

In recent years, low-dimensional lead-free metal halides have attracted extensive attention due to their unique optical properties, low toxicity and excellent environmental stability. In this paper, Cs2ZnCl4 ∶Ce3+, Cs2ZnCl4 ∶Mn2+ and Cs2ZnCl4 ∶Ce3+, Mn2+ microcrystals are prepared by hydrothermal method. The phase and luminescence characteristics of the microcrystals are characterized by X-ray diffractometer and fluorescence spectrometer. In a series of Ce3+ ions doped and Ce3+ and Mn2+ ions co-doped Cs2ZnCl4 microcrystals, Ce3+ ions emit at 254 nm in the ultraviolet region, and its emission peak is at 350 nm, corresponding to the 4f-5d transition of Ce3+ ions. In Cs2ZnCl4 microcrystals doped with Mn2+ ions and Ce3+ and Mn2+ ions, Mn2+ ions all exhibit green light emission in the visible region at 361 nm, and the emission peak is located at 530 nm, which corresponds to the 4 T1→6 A1 transition of Mn2+ ions in tetrahedral environment. In Cs2ZnCl4 microcrystals doped with Ce3+ and Mn2+ ions, the emission spectra of Ce3+ and Mn2+ ions only have their respective luminescence peaks corresponding to their respective excitation peaks, which is a phenomenon of excitation wavelength dependence. In addition, the compound can be applied to fluorescence anti-counterfeiting and information encryption applications in the future because of its obvious excitation wavelength dependence. [ABSTRACT FROM AUTHOR]

Wearing masks has been widely recommended as a way to prevent respiratory diseases amid the normalization of the COVID-19 pandemic. There is a demand for masks that goes beyond simply being filters for aerosols containing microbes, and it can fulfill more needs such as antimicrobial, antiviral, self-cleaning and detection. Masks with antibacterial and antiviral functions can effectively kill pathogens trapped in the filter layer of masks and reduce sources of pollution and infection. Masks with self-cleaning function can realize the recycling of masks, alleviate environmental pollution and resource waste. Masks with self-detection function can realize instant visual detection of pathogens and solve the discomfort caused by routine sampling. Various functional modifications improve the mask's performance, such as metal nanoparticles and herbal extracts to inactivate pathogens. Carbon-based nanoparticles make masks photothermal and superhydrophobic to prolong the life of masks. Metal nanoparticles can be used for pathogen detection by quenching or enhancing their fluorescence. This paper reviews the recent progress in the development and functionalization of functional masks with the advancement of material science in the last three years and the development direction of multifunctional masks is forecasted. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) plastics can be recovered into terephthalic acid (PTA) and ethylene glycol monomers through hydrolysis reactions, and the comprehensive utilization of terephthalic acid has certain research significance. In this paper, Ru/CeO2 catalyzed PTA hydro-conversion reaction is researched. Attempts of generating more oxygen vacancies and Lewis acid sites on Ru/CeO2 by high-temperature reduction in H2 are made for boosting the catalytic activity in PTA hydro-conversion. Ru-based catalysts with pre-reduced CeO2 support exhibits significant enhanced activity in PTA hydro-conversion, as the PTA conversion is raised by 179%~300% under 200~250℃. The enhancement in catalytic activity by reduction pretreatment of CeO2 support is attributed to enhanced adsorption of PTA reactant due to newly generated Lewis acid sites. This work provides useful insights for rational design and precise surface regulation for Ce-based heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Memristor is a basic component of circuit that associates charge with magnetic flux. It is the same as resistance in dimension, which shows nonlinear resistance switching behavior with voltage and current. As a new type of nonvolatile memory devices, memristor has the advantages of simple structure, high storage density, and simulation of biological synapses. Because of its unique ：“memory characteristics”, memristor has been widely studied in the fields of resistive memory devices, neural network, nonlinear computing circuit design and so on. Rare earth oxide-based memristors have been widely researched owing to the stable performance and multiple application prospects. However, there is no comprehensive summary of rare earth oxide-based materials, especially heavy rare earth elements. Therefore, this paper discusses the structure, composition, and resistive switching mechanism of the memristor. Secondly, it systematically reviews the key work of the application of each rare earth element oxide and rare earth doped oxide memristor in resistive memory, artificial neural network, and other aspects, from Y element to Lu element. The performances of rare earth based memristor with different device structures are summarized. Finally, the challenges of the rare earth based memristor are analyzed, the current feasible methods are briefly described, the advantages and disadvantages of rare earth based oxide memristor are summarized, and the development trend and application potential are forecasted. [ABSTRACT FROM AUTHOR]

This paper illustrates how R. B. Woodward introduces physical instruments to organic chemistry， and alteres the way of chemical thinking and organic synthesis. This paper proposes that Woodward changes chemistry from empirical research to rationally planned endeavor， in which chemists begin to investigate the chemical structures and reactivity of molecules with scientific instruments. [ABSTRACT FROM AUTHOR]

Cyclic olefin copolymer (COC) is produced through the copolymerization of ethylene and cyclic olefins, and has been used for the manufacturing of optical devices and diagnostic containers due to its high transparency and excellent water vapor barrier. However, COC with high glass-transition temperature usually needs high cycloolefin insertion in copolymer and has increased brittleness, which has significantly hampered its many end uses. The introduction of α -olefin into ethylene/cycloolefin binary copolymers that have been extensively studied is expected to expand the application of cyclic olefin copolymers. In this paper, we report the terpolymerization of ethylene/norbornene/1-octene and ethylene/dicyclopentadiene/1-octene catalyzed by modified cyclopentadienyl scandium complexes 1−3 activated with [Ph3C] [B (C6F5 ) 4 ] and Ali Bu3 because rare earth catalysts have shown excellent catalytic performance towards olefin polymerization. These rare earth catalysts exhibit high catalytic activities (4. 4×105 ~21. 4×105 g/ (mol (Sc) ·h·bar) ) . The resultant terpolymers show moderate number average molecular weight (Mn=3. 8×104 ~20. 3×104 ) and relatively narrow polydispersity index (PDI=1. 2~2. 4) . The introduction of 1-octene significantly improves the toughness of ethylene/norbornene/1-octene terpolymers, and the P3 sample (Mn 13. 7×104, norbornene 37. 1%, 1-octene 11. 0%) exhibits 2. 0 times higher elongation at break (29. 9% vs. 9. 9%) than the P1 sample (Mn 14. 0×104, NB 42. 6%, OCT 6. 4%) [ABSTRACT FROM AUTHOR]

This paper aimed to conduct systematic bibliometric and visual analysis of graphene oxide（GO） status, and to explore the development status, research hotspots and frontier trends. CNKI database was used as the data source to retrieve the literature related to GO, and the bibliometric method was used for statistical analysis. A total of 2728 articles were included in this study, and the relevant studies showed a trend of “rising-slow decline”. The institutions with relatively high literature output are science and engineering colleges, indicating that the degree of specialization and intensification in this research field is relatively high. The keywords formed five categories, which were clustered by basic research on GO, preparation and reduction of GO, photocatalytic performance, electrochemical performance and mechanical properties, and made full use of GO characteristic analysis to describe the research hotspots in this field. The frontiers of GO research include： finding more ways to synthesize polymers and GO to improve the electrochemical performance of composites, GO composites adsorbing pollutants for sewage treatment, and using electrochemical reduction to prepare graphene using GO. GO has been widely used and has excellent performance in recent years, which is worthy of further exploration by relevant researchers to expand its application in the field of environment and chemistry [ABSTRACT FROM AUTHOR]

Rubber and plastic materials are commonly used in the manufacturing of athletic shoes. This paper summarizes the basic properties of natural rubber, styrene butadiene rubber, nitrile rubber, neoprene rubber, butadiene rubber, recycled rubber, polyvinyl chloride, polyolefin elastomer, styrene-butadienestyrene elastomer, vinyl acetate copolymer, polyurethane, block polyetheramide resin and other materials in the manufacturing process of athletic shoes. The research progress of related rubber and plastic materials in recent years is reviewed. It is pointed out that the rubber and plastic materials for athletic shoes will be developed towards lightweight, functionality, intelligence and environmental-benign in the future. [ABSTRACT FROM AUTHOR]

Due to excellent physical and chemical properties, precious metals are widely used in various fields of national economy and national defense construction, and are extremely important economic and strategic resources. In recent years, due to the rapid growth in the demand for rare and precious metals, the contradiction between supply and demand has become increasingly serious. Therefore, it is very important to selective recovery of precious metals from secondary resources such as electronic waste with high precious metal content. Ion-imprinted polymers (IIPs) are widely used in solid phase extraction, pre-concentration, water treatment, membrane separation and electrochemical sensors due to the advantages of simple preparation, cavity fixation, structural stability, good environmental adaptability, high regeneration capacity and selectivity for template ions. In this paper, the research progress of ion imprinting technology in the recovery of precious metals at home and abroad in recent years is reviewed, the preparation process and its application are introduced, and the current problems and future development directions of precious metal ion imprinting technology are analyzed and prospected. [ABSTRACT FROM AUTHOR]

Glyphosate, also known as N-(methyl phosphate)-glycine, is an organophosphorus pesticide with appreciable herbicidal activity. During its production process, a waste stream composed of complex components (glyphosate wastewater) is produced with the feature of abundant organic matter and high salinity, which obstructs the harmless treatment and resource utilization of glyphosate wastewater. In this paper, the principle and performance of several methods to treat glyphosate wastewater, such as incineration, advanced oxidation, adsorption, chemical precipitation, and membrane separation technology, are introduced, and their advantages and disadvantages are summarized. Incineration, advanced oxidation technology and biochemical treatment of glyphosate wastewater have low selectivity, which is not conducive to the resource utilization of glyphosate wastewater. In view of limited capacity of adsorption, developing the adsorbents possessing large adsorption capacity is urgently needed for the adsorption method in the industrial application of glyphosate waste treatment. chemical precipitation method exhibits excellent separation performance for the phosphate components even in the severe environment of high salt and high COD, whereas it produces a considerable amount of sludge with complex composition. Membrane separation method has been extensively applied to remove impurities in the waste stream and effectively recover valuable compositions, whereas the mere use of membrane technology could not meet the treatment demand due to the complexity of glyphosate wastewater. In this regard, new types of membrane technologies, such as liquid membrane separation and polymer inclusion membrane technology, have been developed. In terms of a variety of advantages including appreciable stability, longlifespan, easy operation and small footprint, the newly developed membrane separation technologies exhibit their prospectsingreen and economic treatment oforganic wastewater containing high salt and recycling of valuable composition. [ABSTRACT FROM AUTHOR]

In this paper, a random copolymer of N, N-dimethylacrylamide and N-isopropylacrylamide (P (DMA-coNIPAM) ) as well as poly-N, N-dimethylacrylamide (PDMA) are synthesized and blended to prepare a composite sieving medium for non-gel capillary electrophoresis, aiming to reduce the viscosity of the sieving medium while enhance its DNA separation performance. Analyses by NMR spectroscopy and Fourier transform infrared FT-IR) spectroscopy confirm that both polymers are successfully synthesized. The hydrodynamic diameter, low shear viscosity and UV-Vis absorbance results show that P (DMA-co-NIPAM) is thermoresponsive with a low critical solution temperature (LCST) of 60~80 ℃ . DNA sieving results indicate that the composite medium containing 10% P (DMA-co-NIPAM) exhibits best properties, a viscosity 19% lower than PDMA and a higher resolution and theoretical plate number in separating large DNA fragments, and separation time is reduced by more than 4%, showing good separation performance. [ABSTRACT FROM AUTHOR]

Transition metal phosphate has attracted the attention of researchers in the field of electrolytic water because of its advantages of safety， cleanliness， low cost and high efficiency. Phosphate groups in phosphate have unique atomic geometric structure， strong coordination and various orientations， which are beneficial to stabilize the middle valence state of transition metals and accelerate proton conduction rate. However， its poor conductivity and low porosity have prompted researchers to explore and design more efficient transition metal phosphate electrocatalysts. Although researchers have invested a lot of time and energy， there are still many problems to be solved in the efficient development and utilization of transition metal phosphate electrocatalysts. In this paper， combined with the latest research progress of transition metal phosphate electrocatalysts， the development and design strategies of phosphate by researchers in recent years are introduced from the aspects of morphology control， defect engineering and interface engineering. At the same time， the opportunities and challenges faced by this kind of catalyst in the future material field are discussed from the aspects of scientific research and practical application. [ABSTRACT FROM AUTHOR]

With the increasing demand for green and efficient energy storage devices， advanced technologies for clean energy conversion have attracted close attention from researchers. Fuel cells with environmental friendliness and high energy conversion efficiency are promising alternatives to traditional energy sources. However， Pt catalysts with high commercialization degrees in the industrial catalysis field have some problems， such as high cost， poor stability and weak anti-toxicity ability， which limits the further development of fuel cells. The development of non-Pt oxygen reduction reaction （ORR） catalysts with abundant reserves， low cost and excellent performance is an effective way to improve the efficiency of fuel cells. In this paper， based on the research results at home and abroad in recent years， various types of non-Pt system ORR catalysts， including non-precious metal and non-metal catalysts， are systematically introduced. The advantages， disadvantages and modification strategies of various catalysts are summarized， and challenges and prospects for the development of ORR electrocatalysts are put forward. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction （ORR） is an important cathode reaction for metal-air batteries and proton exchange membrane fuel cells （PEMFCs）. It is of great significance to study non-noble metal catalysts with high activity and stability. In this paper， MIL-101（- Al-Fe） with hierarchical porous structure is innovatively used as the metal precursor template， and Fe-N-C catalysts with rich mesoporous structure are successfully prepared. Electrochemical test results show that Fe-N-C-MIL-900 shows the best ORR activity with half-wave potential of 0. 905 V in 0. 1 mol/L KOH electrolyte. The ORR electron transfer number of Fe-N-C-MIL-900 catalyst is 3. 98， and the H2O2 yield is less than 3%， demonstrating an obvious 4-electron ORR pathway. This work provides a new way to prepare hierarchically porous Fe-N-C catalysts with high ORR activity. [ABSTRACT FROM AUTHOR]

Among many hydrogen production technologies， electrolysis of water has many obvious advantages， such as environmentally friendly， simple and easy to operate. Industrial-scale hydrogen production is typically carried out at high current density. A great number of H2 bubbles will generate on the electrode surface during the process of hydrogen production. The aggregation and adhesion of bubbles on the electrode surface will lead to a large number of active sites being covered， resulting in the reduction of the efficiency. Therefore， regulating bubble wetting behavior is crucial for industrial electrolysis of water. In recent years， superaerophobic materials have attracted much attention due to their unique wetting capabilities. Superwetting interface materials can be constructed by controlling the chemical composition of the electrode surface and constructing rough structure at micro and nano scales. This type of material has a superhydrophilic/superaerophobic interface structure， which facilitates the effective infiltration of aqueous electrolyte and accelerates the release of in-situ generated bubbles， thus enhancing the water splitting performance of the catalyst. This paper systematically introduces the water splitting catalysts with superhydrophilic/superaerophobic interfacial structures reported in recent years， outlines the synthetic design strategies and catalytic performance of the catalysts， and the current research status， challenges and application prospects of superwetting water splitting catalysts are summarized and prospected. [ABSTRACT FROM AUTHOR]

In recent years, with the continuous growth of coal-fired power generation in China, as the most important solid waste of coal-fired power plants, the emission of fly ash has also increased sharply with the growth of coal consumption. Fly ash is a by-product of burning coal in coal-fired power stations. Large amounts have been discharged from power plants and dumped on reclaimed land or into the sea, posing potential risks to the environment around these areas and causing serious social and environmental problems. On the other hand, the content of aluminum and silicon elements in fly ash is very high, which has a very high extraction value. Due to the special physical and chemical properties of hydrogen, physical adsorption storage of hydrogen energy has the advantages of safety and reliability, rapid adsorption and desorption of hydrogen under mild conditions. In this paper, ZSM-5 zeolite with high crystallinity is directly synthesized by hydrothermal synthesis using fly ash pretreatment and its hydrogen storage performance is studied. [ABSTRACT FROM AUTHOR]

In order to establish a complete and objective evaluation method in theory for property, a systematic study of silicone acrylic emulsion is carried out in this paper. The thermal stability, structure, morphology and particle size of silicone acrylic emulsion are characterized and analyzed. The relationship between the concentration of silicone acrylic emulsion with its viscosity and surface tension is investigated. In addition, to further verify the properties, the silicone acrylic emulsion is used for repairing the flaking and disrupting murals. The results show that the silicon acrylic emulsion is amorphous, the particles are nearly spherical without agglomeration, and its average particle size is 190 nm. The thermal stability and thermal aging resistance are improved effectively due to the introduction of Si-O-Si bond. With the increase of silicon-acrylic emulsion concentration, the surface tension decreases and the relative viscosity increases. Silicon-acrylic emulsion has good mechanical stability, storage stability, thermal stability and salt tolerance. Silicon-acrylic emulsion is used for restoration of the flaking and disrupting murals as cementing materials after aging experiment in various conditions. It is shown that silicone acrylic emulsion is a suitable material for mural conservation. All results indicate that silicon-acrylic emulsion can be used as a kind of excellent cementing material in repairing the flaking and disrupting mural. [ABSTRACT FROM AUTHOR]

Traditional industrial nitrogen fixation (NF) process uses the Haber-Bosch process which requires high temperature and high pressure, causing high energy consumption and serious pollution. Gliding arc plasma (GAP) combines the advantages of thermal plasma and cold plasma, which can efficiently produce active species and improve energy efficiency obviously. It has great application potential in the field of NF, and has received extensive attention in recent years. However, the research on NF via GAP is relatively fragmented at present. It is necessary to summarize the specific content. The research progress of NF via GAP at home and abroad in past 10 years is reviewed in this paper, mainly including GAP discharge mechanism, reactor design, process parameters and NF reaction mechanism. GAP discharge has B-G mode with breakdown following gliding discharge and A-G mode with continuous steady discharge. A-G mode discharge helps to improve nitrogen fixation efficiency. With the continuous development of GAP discharge technology, the electrode structure in GAP reactor has evolved from the traditional 2D blade structure to a variety of 3D cylindrical structures. Based on process optimization, GAP facilitates the vibrational excitation of N2 molecules, thereby promoting the splitting and transformation of N2 molecules. In the last, the research on NF through GAP is prospected. [ABSTRACT FROM AUTHOR]

Gunpowder is one of the four great inventions of ancient China, which once had an important impact on the world pattern and development process. However, after the late Ming Dynasty and the early Qing Dynasty, gunpowder firearms gradually declined in China. Gunpowder moved to the West with the war and became black powder, which promoted the birth and development of modern chemical science. The development of chemical science is of great significance to the dynamite family. The brilliant achievements of China's modern king of dynamite revitalize the glory of Chinese gunpowder. This paper reviews the legendary development course and the groundbreaking role of dynamite, describes the properties, rich types and unique working principles of its special chemical energy, and tries to trace the internal mechanism of gunpowder combustion and explosion. It aims to highlight the importance of scientific thinking mode and the development of chemistry discipline to the study of explosives, so as to continuously enrich the knowledge connotation of chemistry students, stimulate their enthusiasm for innovative thinking, enhance their professional confidence, cultural confidence and national confidence, and promote the spirit of scientists. [ABSTRACT FROM AUTHOR]

Propylene is a basic chemical raw material and the demand of which has been increasing in recent years, however, the traditional process such as steam cracking and catalytic cracking cannot meet the demand of propylene. Propane dehydrogenation （PDH） process has attracted extensive attention due to its wide sources of raw materials, high selectivity of propylene and easy separation of products. Traditional PDH catalysts are Pt-Sn/Al2O3 and CrOx /Al2O3, however, the platinum-based catalyst is expensive, and the chromium based catalyst has high toxicity. The bulk metal oxides （ZrO2, Al2O3, TiO2, WO3, Eu2O3 and Gd2O3） have the advantages of high intrinsic activity, low price, non-toxicity and environmental protection, exhibiting good application prospects. Based on this, this paper reviews the research progress of propane dehydrogenation from two aspects： the mechanism of PDH and the regulation of structure and properties for bulk metal oxide catalysts. It is summarized that coordinative unsaturated metal cation （M ） is the main dehydrogenation active site, and its concentration can be regulated by crystallite size, crystal phase, metal doping, noble metal nanoparticles loading, reducing gas （H2, CO） pretreatment, and so on. Finally, it is pointed out that the coupling of other dehydrogenation active sites （metals or metal oxides） on the basis of bulk metal oxides is an effective way to further improve the catalytic performance of PDH. [ABSTRACT FROM AUTHOR]

Sulfuric acid, nitric acid, phosphoric acid and perchloric acid are usually used as catalysts for the preparation of organic peroxides. Due to the corrosion of strong acid to the equipment, the catalyst can not be reused, the amount of waste water after treatment is large, and the post-treatment cost is very high. The preparation of organic peroxides with heterogeneous catalysts has been paid more and more attention. Heterogeneous catalysts have the advantages of high activity, good stability and reusability, simple posttreatment, less equipment corrosion, and less environmental pollution. In this paper, on the basis of a brief introduction of the homogeneous preparation process of organic peroxides, the heterogeneous catalysts for the preparation of organic peroxides, including ion exchange resins, molecular sieves, phase transfer catalysts, metal oxides, polymer carrier catalysts and carbon-based support catalysts are summarized. The reactors and preparation processes are discussed, and the development direction of heterogeneous catalytic synthesis of organic peroxides is described. The study has strong reference value and guiding significance for understanding the progress in the preparation of organic compounds by heterogeneous catalysis, developing heterogeneous catalysts with excellent performance, and optimizing the production process of organic peroxides. [ABSTRACT FROM AUTHOR]

Based on the demands for green manufacturing, energy conservation and environmental protection, the developing tendency of pressure-sensitive adhesive is focused on high performance, solvent-free, and biodegradability at home and abroad. The rheological and bonding properties of chlorosulfonation modified poly (propylene carbonate）（MPPC) are studied in this paper. The results show that the bonding properties and peeling strength of MPPC are strongly dependent on the number of average molecular mass. When the number average molecular mass of MPPC ranges from 7600 to 17500, the tensile lap-shear strength increases from （0. 35±0. 11) MPa to （3. 78±0. 33） MPa with the increase of the number average molecular mass of MPPC. The higher the number average molecular mass of MPPC, the higher the tensile lap-shear strength. At the same time, MPPC peel strength data also show the same trend, namely a high number of average molecular mass MPPC with high 180（°） peel strength, which can be applied to high-performance pressure sensitive adhesive materials. The results of rheological data further prove that the energy storage modulus （G'） and loss modulus （G"） of a high number average molecular mass MPPC are higher than those of MPPC with a low number average molecular mass. This provides a theoretical basis for preparing biodegradable pressuresensitive adhesives based on PPC. [ABSTRACT FROM AUTHOR]

In this paper, titanate nanotubes (TNTs) are prepared by hydrothermal method, and then the titanate nanotubes (TNTs-LA) are modified with lipoic acid by impregnation method. The structure of TNTs-LA is characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FT-IR), and the adsorption performance of methylene blue (MB) is evaluated. The results show that the adsorption performance of titanate nanotubes modified with lipoic acid is obviously enhanced. The removal of MB is also related to the pH of solution. The kinetic study shows that the adsorption kinetics of MB by titanate nanotubes accords with the second-order kinetic equation. The maximum adsorption capacity of MB on TNTs-LA is 216. 98 mg/g by Langmuir adsorption isotherm model. [ABSTRACT FROM AUTHOR]

Dye-containing wastewater, largely discharged from the textile or printing industries, is one of the well-known sources of water pollution, posing great threats to both human health and the living environment. Although several water treatment technologies including physisorption, chemical oxidation, and biodegradation have been developed, most of them are costly and may produce some by-products with unknown toxicities. Therefore, it is highly desirable to develop economic and effective treatment technologies to reduce water resource consumption and protect the environment. Photocatalysis is a method in that highly reactive transitory species such as superoxide or hydroxyl radicals can be generated by reacting oxygen or water with photocatalysts upon irradiation of light, then degrading the organic dyes. Because the whole photocatalysis process has no chemical input and no secondary pollutants, it is considered to be an environmentally friendly, energy-efficient, and sustainable technique. In this paper, we have reviewed different kinds of photocatalyst systems developed in recent ten years for the degradation of organic pollutes, which cover inorganic semiconductors, metal-organic frameworks, organic small molecules, and conjugated porous polymers. Based on the large surface area and high photocatalytic activity, the conjugated porous polymers can simultaneously adsorb and photodegrade organic dyes under visible light, exhibiting stronger developmental potential compared with other photocatalytic materials. [ABSTRACT FROM AUTHOR]

In recent years, some halogen-based flame retardants have been gradually eliminated out for consideration of the environment， and phosphorus-containing flame retardants have received extensive attention as substitutes for halogen-based flame retardants. However, efficient phosphorus-based flame retardants usually produce more smoke while improving flame retardancy, therefore, they need to be used in combination with synergists. This paper introduced the flame-retardant mechanism of phosphorus-containing flame retardants in epoxy resin. The latest research progress of synergists， including inorganic， organic， and organic-inorganic hybrid synergistic agents， with phosphorus-based flame retardants in epoxy resin was summarized. We look forward to the future development trend of the synergistic system of phosphorus-containing flame retardants in epoxy resin. [ABSTRACT FROM AUTHOR]

AB2 hydrogen storage alloy has attracted extensive research interest due to its advantages of high theoretical hydrogen storage capacity， long cycle life and high cost performance. However， AB2 hydrogen storage alloy has some disadvantages such as activation difficulty， toxicity and high platform， which hinders its practical application. In recent years， aiming at the defects of AB2 alloy， researchers have carried out a lot of modification studies and made great progress. This paper summarizes the research progress of AB2-type hydrogen storage alloys in the past 30 years， focuses on the methods to improve its hydrogen storage performance， and puts forward the key research directions of AB2-type alloys in the future. [ABSTRACT FROM AUTHOR]

Silicon （Si） has become the most promising anode material for the next generation lithium-ion battery because of its ultra-high theoretical specific capacity. However， the intercalation and removal of lithium-ions will cause a great change in the volume of silicon microparticles (SiMP)， which will lead to the pulverization of SiMP and irreversible attenuation of electrode capacity， which seriously limits the wide application of silicon based materials. A large number of reports in the past have shown that polymer binder can effectively overcome the “island effect” caused by the volume expansion of SiMP . It could maintain the integrity of the electrode in the charge-discharge process， and then improve the electrochemical performance of the electrode. According to the structure classification of polymer binders， they can be roughly divided into four categories， linear， branched， cross-linked and conjugated. When the binders with different molecular structures are used as silicon-based negative electrode， the electrodes show different electrochemical properties. Particularly， when polymer binders with multiple molecular structures are designed， the practical application of silicon-based negative electrodes will be greatly promoted. By analyzing the effects of various polymer binders on the electrochemical properties of silicon anode， the differences of binders with different molecular structures can be clearly obtained， and then provide ideas for the development of silicon anode polymer binder in the future. Finally， this paper proposes the design direction of the next-generation polymer binder to promote its development towards large-scale application and industrial production. [ABSTRACT FROM AUTHOR]

In the context of the development of new energy sources to reduce carbon emissions and achieve carbon neutralization, power batteries represented by lithium-ion batteries are given higher expectations. The development of electrode materials with high capacity, high multiplicity and high stability is a key step to achieve this goal. Graphite cathodes and silicon carbon cathodes are relatively mature at present, and maintain their respective advantages. Black phosphorus has two-dimensional layered structure and high lithium potential, which shows outstanding advantages in realizing extremely fast charging, but there are also some problems such as volume expansion. In view of the problems of black phosphorus anode, researchers studied the optimization from various dimensions, including structure optimization, surface interface optimization and the pre-lithiation strategy. In this paper, the possibility that black phosphorus can be used as anode electrode of extremely fast charging lithium ion battery is demonstrated, the optimization progress of black phosphorus negative electrode is then reviewed, and its own views and suggestions are put forward. The challenges and development direction of black phosphorus anode electrode are pointed out, and the development prospect of black phosphorus anode electrode is prospected. [ABSTRACT FROM AUTHOR]

Neurodegenerative disease is a kind of neurological dysfunction disease caused by the progressive lesion or loss of specific nerve cells in the nervous system. With the aging of the global population， its incidence is increasing significantly. At present， the pathogenesis of such diseases is not clear， and there is a lack of effective clinical treatment measures. Ginseng contains a variety of active ingredients and has a very wide range of pharmacological effects in the treatment of neurodegenerative diseases. Based on recent literature reports， this paper first summarizes the active ingredients of ginseng and detection methods. Then， the specific pharmacological effects of ginseng in the prevention and treatment of neurodegenerative diseases are summarized. Finally， the related mechanisms and pathways are summarized and reviewed. At present， there are many kinds of chemical components with preventive and therapeutic activities for neurodegenerative diseases， but more active components and clinical application research still need to be further studied. [ABSTRACT FROM AUTHOR]

Heavy metals are difficult to biodegrade and pose a serious threat to the environment and human life and health. Hence， the detection and treatment of heavy metal pollution is vital. In recent years， electrochemical methods for the detection of heavy metal ions have become a research hotspot in the field of heavy metal detection because of their high sensitivity， fast analysis speed and the ability to detect multiple metal ions simultaneously. This paper reviews the detection principles and development status of common electrochemical detection methods， and describes the detection effects of potentiometric analysis， potentiometric stripping analysis and voltammetry by introducing the parameters of linear range， detection limit and recovery. Finally， the review outlines the advantages and disadvantages of various methods， and points out the future research directions in order to provide a basis for the application of electrochemical sensors. [ABSTRACT FROM AUTHOR]

The growing demand for energy is driving the development of renewable and efficient energy materialsdue to the high consumption of fossil fuels. Hydrogen is considered as a potential energy carrier because of its abundant earth sources and clean burning. The preparation of clean and renewable hydrogen by hydrolyzing ammonia borane is one of the effective ways to solve energy problems. The development of efficient and safe catalysts has been the focus and hotspot in this field. Metal-organic framework materials (MOFs) are widely used in ammonia borane hydrolysis for hydrogen production due to their unique structural composition. This paper focuses on the role of MOFs materials in catalyst preparation and summarizes the role of different MOFs materials in catalytic hydrogen production by ammonia borane hydrolysis. In addition, the current problems are summarized and the future development of this field is pointed out. [ABSTRACT FROM AUTHOR]

In recent years, rare-earth-doped up-conversion luminescent materials have received increasing attention in solar cells, industrial lighting, and medical fields. The current research is mainly to find new and efficient rare-earth up-conversion luminescent materials. For the study of luminescent materials, the choice of matrix is particularly important. Molybdate stands out from many matrixes due to its stable physical and chemical properties and low phonon energy. In this paper, molybdate is selected as the matrix material doped with rare earth ions. Tm and Yb ion-doped NaGd (MoO4)2 samples are prepared by hydrothermal method, and the change of the luminescence characteristics of NaGd (MoO4)2 phosphor is explored by changing the ion doping concentration. Through the analysis of its spectrum, it is found that under 980 nm laser irradiation, NaGd (MO4)2: Yb3+/Tm3+ has a blue emission peak at 477 nm and a red emission peak at 648 nm. When the doping mole fraction of fixed Yb3+ is 6% and the doping mole fraction of Tm3+ is changed to 0, 0. 5%, 1% and 2% respectively, it is found that with the increase of the doping mole fraction of Tm3+, the intensity of the emission peak at 477 nm first increases and then decreases. When the doping mole fraction of Tm3+ is 0. 5%, the luminous intensity of molybdate phosphor first increases and then decreases to the maximum. It has broad prospects in the application of multi-color lighting and light source devices. [ABSTRACT FROM AUTHOR]