Eutrophication becomes more serious with the development of society. It is difficult for the conventional sewage treatment technology to meet the requirements of environmental treatment. Efficient and economical deep nitrogen and phosphorus removal technology becomes a necessity. Biological method is often used for nitrogen removal, and physicochemical method is effective for phosphorus removal. The technology of biological denitrification for nitrogen removal is mature and widely used. For phosphorus removal, chemical precipitation usually requires additional structures and may cause secondary pollution. Physical adsorption has some disadvantages of low saturated adsorption capacity and high cost. Therefore, the potential application of some industrial solid and mineral wastes with high activity, low cost and environmental friendliness has attracted recent attentions. The development of phosphorus removal materials based on solid waste is a current research hotspot. Compared with the conventional physicochemical method, the crystallization method can reduce the structure and facilitate the recovery of phosphorus. Phosphate ore in China is rich, and the massive mine tailings after processing are piled up at will due to the improper development, resulting in environmental pollution and resource waste. Collophanite is in apatite, which can be used as a crystal seed of phosphorus removal by crystallization method. This way can reduce the cost, and realize the resource utilization of waste. In the early stage, low-grade collophanite as a mineral waste was used for deep phosphorus removal in sewage. This paper was to explore a possibility of simultaneous nitrogen and phosphorus removal in one reactor via physicochemical and biochemical processes. A low-grade collophanite was used as a denitrification filter, which acted as a carrier of denitrification microorganism attachment and growth and provided an apatite crystal seed. Effect of mineral fillers on the simultaneous nitrogen and phosphorus removal was investigated.

Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic aromatic compounds consisting of two or more condensed benzene rings, having greater teratogenicity, carcinogenicity, mutagenicity and toxicity. The most representative PAHs is benzo(a)pyrene (B[a]p), which is composed of five benzene rings, and is classified as a Group I carcinogen. The treatment technologies for B[a]p removal include bioremediation, physical remediation and chemical remediation. The advanced oxidation technology based on sulfate radicals becomes a recent research hotspot because of its high redox potential, high reactivity and environmental friendliness. Nevertheless, persulfate needs to be activated through various approaches to produce a series of reactive species, and iron-based materials are widely used due to the abundant reserves, environmental friendliness and excellent activation performance. In this paper, pyrite (FeS2) was used as a cheap and non-toxic sulfide mineral, allowing for a slow release of Fe2+ as well as the cycling of Fe2+ and Fe3+. Kaolinite was chosen as a suitable carrier to solve the agglomeration of FeS2 nanoparticles. A composite with FeS2 and kaolinite was prepared to obtain efficient persulfate activation and B[a]p degradation.

In China, thousands of tons of highly toxic hexavalent Cr slags are produced annually. The existing remediation technologies face challenges due to the facile oxidation, “re-yellowing” effects, and contamination from iron additives, hindering the achievement of sustained governance and resource recycling for Cr pollution. This study conducted microbial mineralization experiments on soil at actual Cr-contaminated sites, delving into the stability, recyclability, and reaction mechanisms of mineralization products. The results indicate that this method can efficiently reduce Cr6+ and Fe3+ in Cr slag to form precipitates. After 60 d extensive air exposure, the mineralized products exhibited little reoxidation or re-decomposition, and demonstrated weak magnetism, indicating a potential for recovery by magnetic separation. This paper was to investigate a low-cost, efficient in-situ, and long-term governance solution for treatment of Cr pollution on-site and facilitation of the recovery and reuse of Cr resources.

Electrokinetic remediation is a promising method for Cr(VI) treatment. Electrokinetic remediation operates based on a low-intensity electric field across the soil, which mobilizes contaminants towards the electrodes. Some previous studies tried to improve the mobility and availability of contaminants for extraction. However, the technology faces some challenges such as interference from non-target contaminants. It is thus necessary to develop the electrokinetic remediation with other technologies like chemical agents and permeable reactive barriers. Some minerals can be used to remediate Cr(VI) due to their properties like surface effect and redox effect. The existing researches on minerals for Cr(VI) remediation mainly focus on zero-valent iron (ZVI) materials.ZVI usually requires loading materials to minimize agglomeration. In this paper, a magnetite/pyrrhotite composite material (i.e.,pyrrhotite naturally dispersed in magnetite) was introduced to the electrokinetic remediation systems, mitigating shortage of electron donors in Cr(VI) contaminants and stabilizing Cr in the form of Cr-containing minerals. The impacts of mineral filling position and potential gradient on the Cr(VI) remediation performance were investigated, and the Cr-containing products were analyzed.

Montmorillonite (MMT) nanosheets with large sizes is significant for controllable preparation of MMT functional nanocomposite materials. Compared with MMT, two-dimensional MMT nanosheets have a larger specific surface area, higher aspect ratio and richer hydroxyl groups at the edges. Therefore, MMT nanosheets are widely applied in the fields like environmental remediation, energy storage, flame retardant and membrane materials. The methods for preparing two-dimensional MMT nanosheets include mechanical milling, shearing, intercalation and ultrasonic exfoliation. However, the size of MMT nanosheets can be seriously damaged because of the higher external energy input of these exfoliation methods, thus affecting the applications. It is thus necessary to propose a new method for preparing MMT nanosheets with large sizes. In this paper, a method of MMT exfoliation was investigated based on its nature of osmotic hydration through weakening the interlayer binding energy of MMT. The exfoliation mechanism of MMT based on osmotic hydration was revealed via the conductivity analysis and molecular simulation. In addition, the regulation mechanism of exfoliation was also explored through the regulation of the water consumption and the concentration of MMT suspension during the osmotic hydration.

The extraction and utilization of coal inevitably lead to the generation of significant solid waste, including coal gangue. This byproduct is rich in kaolin mineral resources, and their effective utilization presents a critical strategy for the management of such a bulk solid waste, offering substantial environmental and economic benefits. The processing methodologies are often hindered by the inherent mineralogical properties of the materials. Kaolinite minerals are central to the chemical reactivity in calcined coal kaolin clay, the content and characteristics of kaolinite can vary significantly in different coal kaolin sources due to the diversity in coal-forming geological conditions. It is thus necessary to clarify the mineralogical properties of kaolinite from various sources for the innovative application of coal gangue. In this paper, a high-iron coal-series kaolin clay was analyzed. In addition, the impact of mineralogical properties on the thermal activation and preparation of calcined kaolin clay was also investigated.

Mycotoxins are secondary metabolites with a high toxicity produced by fungi and widely exist in feeding, thus reducing feed quality and affecting human-being and animal health. Montmorillonite as a feed additive can effectively reduce the risk of mycotoxin absorption by organisms, but its surface is highly hydrophilic, and the binding rate with weak/non-polar mycotoxins(such as OTA) is low. In this paper, OTA/montmorillonite composite adsorption material (i.e., CPC-MT) was prepared with pyridine salt CPC as a modifier. Its structure before and after montmorillonite modification was analyzed. The OTA adsorption behavior of modified montmorillonite was investigated through batch adsorption experiments combined with kinetic and isothermal adsorption models, so as to provide a technical scheme for effective adsorption of mycotoxins in feed.

Red mud is a solid waste generated from alumina production, its massive accumulation occupying extensive land areas and leaching alkalis and heavy metals, leading to significant environmental issues such as soil alkalization and groundwater pollution. This study responds to the current demand for sponge city construction via innovatively utilizing red mud as a raw material to produce un-sintered aggregates through a novel pelletization process that leverages similarities between red mud and permeable brick materials. High-strength un-sintered permeable bricks were prepared via integrating mixing, molding, and curing techniques.These bricks improve overall compressive strength and permeability, while drastically reducing energy consumption and environmental impact during production. This approach presents a fresh perspective on red mud utilization and sponge city development, promising the environmental and economic benefits.

Zearalenone (ZEN) as an estrogenic fungal toxin produced by Fusarium graminearum widely presents in grains, corn,wheat and their by-products. The presence of ZEN seriously endangers the health of animal and humanbeing due to the reproductive toxicity, immunotoxicity, genotoxicity, carcinogenic and teratogenic effects. The adsorption method is the most effective way to remove ZEN, and the commonly used adsorbents are silicate minerals. Attapulgite is an advantageous resource in China, which is used as a feed material to enhance immune function and antioxidant capacity, promote intestinal health, and improve animal production performance and product quality. However, it is difficult to realize the efficient removal of low polarity and hydrophobic ZEN using hydrophilic and negatively charged attapulgite. It is thus indispensable to modify attapulgite with cationic surfactants to enhance their surface hydrophobicity and adsorption property toward ZEN. Imidazole ionic liquid surfactant CnmimBr has lowercritical micelle concentration, higher adsorption efficiency and better surface properties than conventional surfactants with the same carbon chain length. In this paper, attapulgite was modified with ionic liquid surfactant CnmimBr for the efficient adsorption of ZEN.

Sulfate radical-based advanced oxidation processes (SR-AOPs) are a highly promising technology for water treatment,and their processing capacity is affected by the catalyst. However, the existing catalysts are mostly powder-based and cannot meet the requirements of recovery and mass transfer in practical applications. Catalytic filtration membrane is a functional membrane that combines catalysis and filtration. It provides a support for the catalyst to ensure its recovery, and restricts the reaction to pores, facilitating a close contact between pollutants and active sites, thereby achieving efficient utilization of peroxymonosulfate. Sepiolite is an excellent catalyst carrier because of its excellent thermal stability, great adsorption capacity, and abundant acid-base sites. In addition, sepiolite is a high-quality film-making material with fibers interwoven into a mesh structure in the same or different directions. In the paper, we prepared a CuO/sepiolite catalytic filtration membrane (CuO/sepiolite) with excellent catalytic performance via impregnation-filtering coating-drying-calcination. In addition, the performance and activation mechanism of catalyzing peroxymonosulfate method were also investigated.

Tourmaline is a kind of borosilicate mineral with complex structure and composition, which is used in the fields of functional materials, environmental protection and healthcare. Since the positive and negative charge centers of tourmaline do not coincide, tourmaline has a natural spontaneous polarization that is one of the most important properties, having its application in various fields. In previous studies, the changes of element occupancy, valence proportion of key elements and crystal structure parameters in tourmaline cause the lattice distortion, resulting in a change of spontaneous polarization intensity. It is thus of great significance to reveal the relationship among the composition, structure and property of tourmaline. In this paper, the control path along iron speciation-microstructure-spontaneous polarization of Fe-Mg tourmaline was investigated to clarify the structure-activity relationship dominated by cation occupancy in Y-site of tourmaline and propose the optimal configuration of tourmaline with the excellent performance.

Hydrophobic organic pollutants in industrial wastewater and oil spillage have attracted wide attention. It is thus important to develop a variety of adsorbents like activated carbon, biochar, zeolite, graphene, etc.. However, carbon-based porous materials exhibit poor thermal stability and flammability, having secure risks during high-temperature applications and thermal regeneration processes. Silicon-based porous materials like zeolite are complex to prepare and difficult to effectively remove multiple organic pollutants simultaneously. Montmorillonite-based adsorbents become popular due to their low cost and environmental friendliness. However, montmorillonite as a powder has challenges in practical applications such as clogging, leakage, and recovery difficulties. It is thus effective in converting montmorillonite into fixed-form aerogel materials.Polyurethane sponge (PU) as an ideal substrate for developing porous aerogels can enhance the mechanical properties of the adsorbents due to its biodegradability, affordability, low density, and customizable dimensions. In this paper, low-density,recyclable, and cost-effective organic montmorillonite/polyurethane sponge composite aerogels were prepared via ultrasonic swelling and freeze-drying. The composite aerogel was evaluated for its adsorption/absorption capabilities towards benzene,bisphenol A, nitrobenzene, oils, and organic solvents. In addition, the reusability and flammability characteristics of the aerogel were also analyzed.

The effective utilization of conventional non-metallic minerals and the advancement of high-performance functional mineral materials are pivotal for the transformation and upgrading of non-metallic mineral industry. Halloysite nanotubes (HNT) as natural silico-aluminate minerals with a unique tubular structure have exceptional biocompatibility, robust adsorption capabilities, and distinct surface properties. These features make them ideal for a wide range of applications, including drug delivery, adsorption,catalysis and fire resistance. The hollow tubular structure of HNT has attracted interests, as its lumen of HNT can encapsulate a variety of functional substances, imparting diverse properties and functionalities to composite materials. Moreover, the differential properties between their inner and outer surfaces have ample opportunities for targeted modifications in subsequent applications.However, raw HNT suffers from several drawbacks, such as small specific surface area, uneven size distribution, and susceptibility to surface hydrogen bonding leading to aggregation. To expand their application scope and enhance performance across diverse fields,the structural and surface modifications of HNT are emerged as critical research areas.Some methods such as calcination, acid/alkaline etching, and ultrasound are reported to modulate the tubular structure of HNT.HNT undergoes the phase and crystal structural transformations during calcination. The dehydroxylation and phase segregation of HNT occur at >450 ℃, leading to the formation of amorphous SiO2 and Al2O3. The temperature of >1 000 ℃ causes the disruption of tubular structure, while HNT undergoes a transformation into mullite at 1 200 ℃. Acid/alkaline etching modifies the tubular diameter, surface morphology, and chemical composition of HNT via etching aluminum/silicon on the tube walls. Acids preferentially attack the aluminum octahedral structures within HNT, causing aluminum ions to leach out and form amorphous silica spheres in-situ.Conversely, alkaline preferentially attacks the silicon tetrahedral structures, leading to preferential leaching of silicon and formation of aluminum hydroxide nanosheets. Some previous studies indicated that leaching HNT in phase-segregated state could allow for more thorough removal of aluminum or silicon from the HNT structure. Moreover, HNT with specific length ranges can be obtained via combining ultrasound fragmentation with single viscosity centrifugation processes.Selective surface modifications on the inner, outer, and interlayer surfaces of HNT facilitate the design of functional surfaces. Silanization as a common method for modifying both the inner and outer surfaces of HNT involves the condensation of silane coupling agents with the hydroxyl groups on the HNT surface. Grafting silane coupling agents with different structures enables the specific anchoring of functional groups on the HNT surface. Electrostatic assembly utilizes the surface charge of HNT and the electrostatic attraction between materials carrying opposite charges to load desired substances onto HNT surfaces, thereby enabling the introduction of various functional substances. Intercalation methods allow for the incorporation of organic or inorganic compounds into the interlayer spaces of HNTs without disrupting their interlayer structure, thus expanding interlayer spacing or loading functional substances onto interlayer surfaces. HNT exhibits a significant potential across various domains due to its unique structure and diverse chemical properties. The lumen and excellent biocompatibility make it an effective carrier for drugs and controlled release systems, improving drug stability and availability in biomedical applications. The high specific surface area and dual-surface nature of HNT contribute to exceptional adsorption properties, making it suitable for environmental applications such as water treatment, wastewater management, and heavy metal removal. Surface modifications or doping with transition metals enable HNT to act as catalysts, enhancing chemical reactions and controlling selectivity. With remarkable mechanical, thermal, and chemical characteristics, coupled with non-toxicity and high biocompatibility, HNT serves as nanofillers in food packaging to bolster mechanical strength, thermal stability, and extends the shelf life of perishable goods. Moreover, the heat resistance and flame-retardant properties also render it valuable in the development of high-performance fireproof coatings and composite materials. HNT has a promising potential for applications in emerging materials,energy, environmental protection, pharmaceuticals, and beyond.

Bi2Te3-based alloys are the most well-known thermoelectric materials for room-temperature applications. The existing Bi2Te3-based thermoelectric materials produced commercially are prepared by a zone melting method, resulting in highly oriented materials with high thermoelectric properties. However, the ingots produced by the zone melting method are prone to disintegration due to the weak van der Waals forces between the layers of Te atoms, leading to the poor mechanical properties and the proclivity for fracture during processing and practical applications. It is thus important to improve the mechanical properties and machinability of Bi2Te3-based materials with the excellent thermoelectric properties. This work was to prepare a n-type Bi2Te2.7Se0.3 thermoelectric material via spark plasma sintering combined with hot extrusion (SPS+HE). The parameters affacting hot extrusion process and preparation of n-type Bi2Te2.7Se0.3 materials under different process conditions were optimized, and the thermoelectric performance and mechanical properties were investigated. In addition, the machinability of the extruded Bi2Te2.7Se0.3 material was also analyzed.

Silicon is considered as one of the most promising lithium anode materials due to its high lithium storage capacity.However, the volume expansion effect and semiconductor properties of silicon hinder its practical application. Two effective strategies exist for mitigating this issue, i.e., reducing the size of silicon to nanoscale; and introducing non-active matrices to improve stability and conductivity. In recent decades, the incorporation of iron silicide (FeSi2) with silicon (Si) has attracted much attention due to its high conductivity, mechanical hardness and environmental friendliness. Unfortunately, the Si/FeSi2 nanocomposites are mainly prepared by high-energy ball milling, which has some drawbacks such as low purity, large particle size, and uncontrollable morphology, making it difficult to achieve the commercial application. Porous silica derived from clay minerals is extensively investigated for the preparation of silicon nanoparticles by magnesiothermic reduction. In addition, porous silica has a large specific surface area, which facilitates the effective dispersion and loading of iron oxides. The reduction of iron oxide and silica dioxide to Fe and Si can be achieved by magnesium. In this paper, a natural montmorillonite (Mnt) with a high content of silica (65%, in mass) was utilized as a raw material. Silicon/iron silicide (Si/FeSi2) nanocomposites were synthesized via modification of Mnt (including acid etching and iron loading) and molten salt-assisted magnesiothermic reduction.

The gyroscope operation relies on the electrostatic actuation and capacitance detection between the resonator and the planar electrode, with a typical gap ranging from 20–150 μm. When organic impurities adhere to planar electrode’s surface, gap’s capacitance changes, leading to fluctuations in the excitation detection signal and thereby affecting the accuracy and reliability of the gyroscope. TiO2 thin film can effectively degrade organic pollutants through photocatalytic reactions. However, little research on its application on the surface of high-precision devices has been reported yet. The thickness of the TiO2 thin film affects the generation and effective separation of photo-generated electron-hole pairs, thereby influencing the photocatalytic performance of the TiO2 thin film. It is thus necessary to determine the thickness of the TiO2 thin film on the surface of the planar electrode through experiments. In this paper, a TiO2/Au composite thin film was designed to reduce the adsorption of organic substances on the surface of planar electrode and improve the thin film quality on the planar electrode surface.

β-Ga2O3 as a ultra-wide bandgap semiconductor material with a great development potential has a bandgap width of 4.8 eV, and a theoretical breakdown electric field of 8 MV/cm. Its Baliga advantage value of β-Ga2O3 is also several times greater than that of silicon carbide (SiC) or gallium nitride (GaN). However, the low thermal conductivity of β-Ga2O3 seriously affected the device's heat dissipation and the application in the high-power field. Wafer bonding is an indispensable key technology in semiconductor devices, which enables the formation of new structures, efficient fabrication, device integration, and cost reduction. The silicon substrate with the advantages of low cost and high thermal conductivity is an important substrate material for heterogeneous integrations. SiO2 layer is easily formed on the surface of silicon, and the surface structure of SiO2 consists of a Si–O–Si three-dimensional network structure together with an unsaturated Si–O structure, and the existence of this structure is conducive to reducing the probability of bubble generation, thus improving the quality of the bonding bonding interface, so it is easier to realize the bonding of silicon and β-Ga2O3 by using SiO2 as an intermediate layer. This paper was to analyze the effect of O2 plasma activation on the wafer surface, including changes in contact angle, roughness, and surface chemical composition. In addition, the effect of annealing temperature on the strength and thermal stability of the bond structure and the structure and composition of the β-Ga2O3/SiO2 bond interface was also discussed.

Relying on their advantages of high water reducing rate, low dosage, and strong molecular structure design ability, polycarboxylate superplasticizers (PCEs) have become the most widely used admixture in the field of concrete admixtures. Adsorption of PCEs onto the surfaces of cement particles is the prerequisite for the dispersing performance of PCE molecules. Therefore, the influences of PCE molecules with different structures on the dispersion properties of cement slurry can be understood by revealing the adsorption process of PCE and the conformation characteristics of PCE after adsorption.It should be noted that both the adsorption process and the conformation of the adsorbed PCE involve interfacial interactions between the organic and inorganic phases, which is the dominant factor determining the overall properties of the material. Recently, molecular dynamics (MD) simulations have been applied to the PCEs to elucidate its working mechanism. However, the molecular size of these model PCEs was much smaller than those typically used for industrial applications in order to reduce computation cost. Furthermore, only pure water was used, or only Na+, Ca2+ and Cl? were additionally added to mimic a cement pore solution. The above methods make the results unable to accurately reflect the adsorption mechanism of PCE. Therefore, to better understand and effectively control the performance of PCE, more in-depth studies at the atomic and molecular scales are needed. Our research team innovatively used MD simulations in which the molecular size of the model PCE is consistent with that of PCE commonly used for industrial applications and simulates cement pore solutions. In addition, the adsorption mechanism of sulfonation modification of PCE was studied by combining the structure, dynamics and stability of interfacial connections.

White light emitting diodes directly driven by alternating current (AC-LEDs) become increasingly popular in lighting.However, the harmful flicker occurs because the blue LED chips only work over the threshold voltage. Transparent afterglow phosphor-glass composites are thus proposed as excellent color converters to eliminate the flicker. In this paper,Gd2.94Al2Ga3O12:0.06Ce3+–SiO2 (GdAGG:Ce–SiO2) glass ceramics were prepared via cold isostatic pressing molding and pressureless sintering at a low temperature. The transparency, structures, microscopic morphologies and luminescence properties were investiagted.Besides, the samples were assembled on the commercial blue LED chips or blue laser diodes (LDs) to explore the potential application.

As a kind of high-energy electromagnetic radiation, gamma rays can lead to radiation effect and environmental pollution. To ensure the reliability and safety utilization of gamma radiations in different areas, materials with reliable gamma shielding performances should be developed. The existing efforts are to use glasses as alternative for the conventional radiation shielding materials. As a typical window material, glass itself has attracted wide attention due to its unique chemical and physical advantages. Among them, lead-based radiation shielding materials are widely used in the field of ionizing radiation protection due to their reliable physical properties. In the nuclear industry and high energy physics laboratories, different materials can be used for temporary or permanent shielding. The lead-based glass doped with heavy metal oxide PbO is widely used in the field of radiation shielding for a long time with reliable light transmission properties, which facilitates the observation and monitoring of radiation areas. In this paper, three kinds of transparent silicate glass with different PbO contents were prepared by a high-temperature melting forming method. The gamma-rays protection abilities of the three kinds of glass were investigated through experimental and thermotical methods. The chemical and thermal stability of the glass were also analyzed. In addition, the influence mechanism of the structure and performance differences of the three kinds of glass was also discussed.

Conventional vapor compression cooling technologies become a challenge because of the high global warming risks. In addition,most of the refrigerant fluids working in vapor compression plants is environmentally harmful. The thermoelectric solid-state cooling is realized by electricity without mechanically moving parts or emissions, offering a sustainable solution to overcome the environmental pollution. However, the thermoelectric cooling efficiency is not competitive, compared with the conventional vapor compression cooling. To improve the efficiency of thermoelectric refrigeration and enhance the competitiveness of thermoelectric refrigeration technology, it is of great significance to develop high-performance thermoelectric refrigeration materials.Recent research work fcous on the thermoelectric refrigeration materials like conventional Bi2Te3-based materials, Mg3(Sb,Bi)2-based materials, IV–VI semiconductors at near room temperature, and Bi1–xSbx, CsBi4Te6, FeSb2 alloys at low temperatures.At near room temperatures, Bi2Te3-based alloy is a kind of conventional thermoelectric material, which has excellent thermoelectric properties. The zT value of Bi2Te3-based thermoelectric materials prepared by the Bridgman method or zone melting method is approximately 1. The thermoelectric properties of Bi2Te3-based alloys are greatly improved, and the zT value of Bi2Te3-based thermoelectric materials is increased based on developed concepts, mechanisms and preparation methods. The zT value of some p-type (Bi, Sb)2Te3 is >1.5. The zT value of some n-type Bi2(Te, Se)3 is >1. However, the crust abundance of Te is rather low, the tellurium resources are scattered and the cost is high. Mg3X2 (X=Sb, Bi) compound is a kind of layered Zintl phase, which has the characteristics of “phonon glass-electron crystal (PGEC)”, non-toxicity and high abundance of constituent elements.Recent studies indicate that the band gap of Mg3(Sb, Bi)2 alloy decreases with the increase of Bi content, and the peak value of zT also moves to the near room temperature region. Bi-rich Mg3(Sb, Bi)2 alloy shows the excellent thermoelectric properties in the near room temperature region, which is comparable to the thermoelectric properties of conventional Bi2Te3-based materials. The IV–VI compounds such as SnSe have good mid-temperature thermoelectric properties and extremely competitive thermoelectric properties in the near room temperature region.Bi1–xSbx is one of the low temperature thermoelectric materials, which has good thermoelectric properties in the temperatures below room temperature. Bi1–xSbx single crystal has good low temperature thermoelectric properties, but poor mechanical properties, which is easy to cleavage during use. In recent years, Bi1–xSbx polycrystalline materials are developed, whose the mechanical properties are better than those of single crystals, but the thermoelectric properties are difficult to reach the level of single crystals. CsBi4Te6 is a kind of p-type low-temperature thermoelectric material with the excellent properties, but in the preparation process, element Cs with an intense activity is usually used, and toxic formaldehyde is required for cleaning. FeSb2 is an only deep low-temperature thermoelectric material that shows a good prospect near 50 K, and its deep low-temperature electric transmission performance is excellent, but the thermal conductivity is high, and its deep low-temperature thermoelectric performance needs to be further investigated.

Lithium-ion batteries are considered as the most promising chemical power source due to their high energy density, good safety, and environmental friendliness. As a key component of batteries, anode material plays an important role on the electrochemical performance. Graphite, Li4Ti5O12 and Si-based materials have attracted much attention as anode materials in lithium-ion batteries.Among these materials, graphite has good conductivity, small volume change, high initial coulombic efficiency, and low cost. As a conventional anode material for lithium-ion batteries, graphite is first commercially applied. However, its low theoretical capacity is the main factor restricting the development of high energy density lithium-ion batteries. Li4Ti5O12 anode material is considered to have a great development potential due to its stable structure during lithiation and delithiation processes and good safety. However, its low theoretical capacity and high cost restrict its practical application. Si has a high theoretical capacity, but it has a disadvantage of large volume expansion during lithiation and delithiation processes, resulting in the poor safety of batteries. The composite of Si and carbon materials is considered as an effective strategy for stabilizing electrodes.SiOC is considered as one of the high potential anode materials for lithium-ion batteries due to its excellent properties such as high theoretical specific capacity, good mechanical flexibility and structural stability, and facile structure regulation. However, the low conductivity of SiOC leads to its poor rate performance and cycling ability, thus restricting its development and application in the field of lithium-ion batteries. The composition of SiOC materials can be controlled through optimizing the composition, structure, and pyrolysis conditions of polymer precursors. Carbon material has high specific surface area, high mechanical stability, and excellent electrical conductivity. Composite with SiOC anode materials, the conductivity of SiOC can be improved, accelerating the transfer rate of lithium ions during lithiation and delithiation processes. Carbon material can act as an inert layer to reduce the volume effect of SiOC. SiOC/C composites can improve the conductivity effectively, thereby significantly improving the electrochemical performance of lithium-ion batteries as anode materials.For elucidating the structure of SiOC, this review analyzes the mechanism of lithium ions storage on SiOC anodes. To address the poor conductivity of SiOC, the composite process of graphite, carbon nanotubes, graphene and carbon nanofibers with SiOC anode materials are reviewed. The design of modification based on different carbon materials and between the anode microstructure and electrochemical performance are discussed. The selection of carbon materials is particularly important for the electrochemical performance of SiOC/C composites. Nanocarbon is beneficial to constructing conductive networks, and after composite with SiOC,there are many micro-/meso-pores inside, which enhances the capacitance effect and further improves the electrochemical performance. Therefore, the electrochemical performance of SiOC/nanocarbon composite materials is better than that of SiOC/traditional carbon composite materials. The rate capability and cycling stability of SiOC-based lithium-ions batteries are improved.

Methane reforming based on solid oxide fuel cell (SOFC) is an effective way to realize clean utilization of fossil energy. The direct internal reforming of CH4 is a process of converting methane into more chemically active syngas (i.e., H2 and CO) by SOFC, and then further oxidizing into water and carbon dioxide to produce electricity. The application of CH4 reforming based on SOFC shows some potential advantages. For instance, the internal reforming of CH4 on the SOFC anode is an exothermic reaction, which can directly use the heat generated inside and reduce the continuous supply of external energy. And the chemical energy in the fuel is directly converted into electrical energy without going through multiple energy conversion stages, greatly improving the power generation efficiency. The products of SOFC are only H2O and CO2, and the water vapor in the tail gas can be condensed to capture high–purity CO2, achieving zero carbon emissions. In addition, the high–temperature water vapor can also be used for waste heat utilization to achieve multi–level utilization of energy.However, there is a carbon deposit problem in the case of SOFC using hydrocarbons as a fuel. When hydrocarbon is not fully converted into syngas upstream of SOFC, the fuel is directly introduced into the anode, where the carbon-containing gas is adsorbed, activated and dissociated to form carbon species. Also, O or OH adsorbed on the surface is insufficient, the carbon species diffuses into the catalyst, gradually accumulating and forming carbon deposits. Therefore, the anode pore and the transmission of the anode raw gas and product gas could be blocked, resulting in the failure of SOFC. The severity of which depends on the operating conditions (i.e., temperature, fuel composition and the catalytic performance of the anode material). The existing methods proposed in the literature mainly include that increasing the polarization current to promote the carbon elimination reaction, modifying other metals into the Ni-based anode to form an alloy anode, and adding a catalyst layer on the external surface of the anode. Among them, the addition of catalytic reforming layer on the outer surface of the anode is a recent research hotspot to inhibit carbon deposition. In order to ensure that the added catalyst layer can play an effective role in reforming hydrocarbons, we need to find a suitable catalytic coating to improve the catalyst activity of the reforming reaction. The type of CH4 reforming reaction depends on the added fuel additives, which can be H2O, O2, and CO2, corresponding to dry reforming of methane, wet reforming of methane and partial oxidative reforming, respectively.Besides, carbon deposition on SOFC can be suppressed by optimizing the anode material. Four typical carbon resistant anode materials are summarized. Doped precious metals form bimetallic alloys on Ni-based catalysts, which produce synergistic effect and form small and highly dispersed metal particles, inhibiting the growth of Ni particles and carbon deposition. CeO2-modified Ni-based anodes can promote oxygen mobility and capture massive active oxygen ions to enhance the flow of charge and accelerate the removal of carbon deposited on Ni surface. The Ni-based anodes modified with Ba oxides exhibit excellent WSC and have a high CO2 adsorption capacity, promoting carbon removal. Ni-free anode materials are considered as alternatives to Ni due to their excellent electrical conductivity and low activity in catalyzing C–C bond formation. However, their limited catalytic activity restricts their commercial application.