Applications

Zeolite imidazolium skeleton (ZIFs) materials as a subclass of metal-organic skeletons (MOFs), ZIFs materials combine the high stability of inorganic zeolites and the high specific surface area, high porosity and tunable pore size of MOFs materials, which can be applied to efficient catalytic and separation processes, so ZIFs and their derivatives have good potential for use in catalysis, adsorption and separation, electrochemistry, biosensor and biomedicine and other fields with good application prospects. The following is a case study of the characterization of ZIF molecular sieves using CIQTEK EASY-V series specific surface and pore size analyzer. As shown in Fig. 3 left, the specific surface area of this ZIF molecular sieve is 857.63 m2/g. The material has a large specific surface area which is favorable for the diffusion of reactive substances. From the N2-adsorption and desorption isotherms (Fig. 3, right), it can be seen that there is a sharp increase in adsorption in the low partial pressure region (P/P0 < 0.1), which is attributed to the filling of micropores, indicating that there is a certain amount of microporous structure in the material, and there is a hysteresis loop within the range of P/P0 of about 0.40 to 0.99, which suggests that there is an abundance of mesoporous structure in this ZIF molecular sieve. The SF-pore size distribution graph (Fig. 4, left) shows that the most available pore size of this sample is 0.56 nm. The total pore volume of this ZIF molecular sieve is 0.97 cm3/g, and the microporous volume is 0.64 cm3/g, with 66% of micropores, and the microporous structure can significantly increase the specific surface area of the sample, but the molecular sieve will limit the catalytic activity under certain conditions due to the smaller pore size. However, under certain conditions, the smaller pore size will limit the diffusion rate of the catalytic reaction, which makes the performance of molecular sieve catalyst limited, however, the mesoporous structure can obviously make up for this defect of the microporous structure, so the structure of the combination of microporous-mesoporous can effectively solve the problem of the limitation of the mass transfer capacity of the traditional molecular sieve with a single pore.   Fig. 1 Specific surface area test results (left) and N2-sorption and desorption isotherms (right) for ZIF molecular sieves Fig. 2 SF-pore size distribution (left) and NLDFT-pore size distribution (right) of ZIF molecular sieve

The characterization of copper foil morphology by scanning electron microscopy can help researchers and developers to optimize and improve the preparation process and performance of copper foils to further meet the existing and future quality requirements of high-performance lithium-ion batteries. Wide Range of Copper Applications Copper metal is widely used in lithium-ion batteries and printed circuit boards because of its ductility, high conductivity, ease of processing and low price. Depending on the production process, copper foil can be categorized into calendered copper foil and electrolytic copper foil. Calendered copper foil is made of copper blocks rolled repeatedly, with high purity, low roughness and high mechanical properties, but at a higher cost. Electrolytic copper foil, on the other hand, has the advantage of low cost and is the mainstream copper foil product in the market at present. The specific process of electrolytic copper foil is (1) dissolving copper: dissolve raw copper to form sulfuric acid-copper sulfate electrolyte, and remove impurities through multiple filtration to improve the purity of the electrolyte. (2) Raw foil preparation: usually polished pure titanium rolls as the cathode, through electrodeposition of copper ions in the electrolyte is reduced to the surface of the cathode to form a certain thickness of copper layer. (3) Surface treatment: the raw foil is peeled off from the cathode roll, and then after post-treatment, the finished electrolytic copper foil can be obtained. Figure 1 Electrolytic Copper Foil Production Process Copper Metal in Lithium-ion Batteries Lithium-ion batteries are mainly composed of active materials (cathode material, anode material), diaphragm, electrolyte and conductive collector. Positive potential is high, copper is easy to be oxidized at higher potentials, so copper foil is often used as the anode collector of lithium-ion batteries. The tensile strength, elongation and other properties of copper foil directly affect the performance of lithium-ion batteries. At present, lithium-ion batteries are mainly developed towards the trend of "light and thin", so the performance of electrolytic copper foil also puts forward higher requirements such as ultra-thin, high tensile strength and high elongation. How to effectively improve the electrolytic copper foil process to enhance the mechanical properties of copper foil is the main research direction of copper foil in the future. Suitable additive formulation in the foil making process is the most effective means to regulate the performance of electrolytic copper foil, and qualitative and quantitative research on the effect of additives on the surface morphology and physical properties of electrolytic copper foil has been a research hotspot for scholars at home and abroad. In materials science, the microstructure determines its mechanical properties, and the use of scanning electron microscopy to characterize the changes in the surface micro-m...

Conductive paste is a special functional material with both conductive and bonding properties, widely used in new energy batteries, photovoltaic, electronics, chemical industry, printing, military and aviation and other fields. Conductive paste mainly includes conductive phase, bonding phase and organic carrier, of which the conductive phase is the key material of conductive paste, determining the electrical properties of the paste and the mechanical properties after film formation.   The commonly used materials of conductive phase include metal, metal oxide, carbon materials and conductive polymer materials, etc. It is found that the physical parameters such as specific surface area, pore size and true density of conductive phase materials have an important influence on the conductivity and mechanical properties of the slurry. Therefore, it is particularly important to accurately characterise physical parameters such as specific surface area, pore size distribution and true density of conductive phase materials based on gas adsorption technology. In addition, precise tuning of these parameters can optimise the conductivity of the pastes to meet the requirements of different applications.   01 Conductive paste introduction According to the actual application of different types of conductive paste is not the same, usually according to the different types of conductive phase, can be divided into conductive paste: inorganic conductive paste, organic conductive paste and composite conductive paste. Inorganic conductive paste is divided into metal powder and non-metallic two kinds of metal powder mainly gold, silver, copper, tin and aluminium, etc., non-metallic conductive phase is mainly carbon materials. Organic conductive paste in the conductive phase is mainly conductive polymer materials, which has a smaller density, higher corrosion resistance, better film-forming properties and in a certain range of conductivity adjustable and so on. Composite system conductive paste is currently an important direction of conductive paste research, the purpose is to combine the advantages of inorganic and organic conductive paste, the inorganic conductive phase and organic material support body organic combination, give full play to the advantages of both.   Conductive phase as the main functional phase in the conductive paste, to provide electrical pathway, to achieve electrical properties, its specific surface area, pore size and true density and other physical parameters have a greater impact on its conductive properties.   Specific surface area: the size of the specific surface area is the key factor affecting the conductivity, within a certain range, a larger specific surface area provides more electronic conduction pathways, reducing the resistance, making the conductive paste more conductive. High conductivity is critical in many applications, such as in electronic devices to ensure efficient conduction of circuits.   Pore size: ...

Ceramic materials have a series of characteristics such as high melting point, high hardness, high wear resistance, and oxidation resistance, and are widely used in various fields of national economy such as the electronics industry, automotive industry, textile, chemical industry, and aerospace. The physical properties of ceramic materials depend largely on their microstructure, which is an important application area of SEM.     What are ceramics? Ceramic materials are a class of inorganic non-metallic materials made of natural or synthetic compounds through forming and high-temperature sintering and can be divided into general ceramic materials and special ceramic materials.   Special ceramic materials can be classified according to chemical composition: oxide ceramics, nitride ceramics, carbide ceramics, boride ceramics, silicide ceramics, etc.; according to their characteristics and applications can be divided into structural ceramics and functional ceramics.   Figure 1 Microscopic morphology of boron nitride ceramics   SEM helps to study the properties of ceramic materials   With the continuous development of society and science and technology, people's requirements for materials have been increasing, which requires a deeper understanding of the various physical and chemical properties of ceramics. The physical properties of ceramic materials are largely dependent on their microstructure [1], and SEM images are widely used in ceramic materials and other research fields because of their high resolution, wide adjustable magnification range, and stereoscopic imaging. The CIQTEK Field Emission Scanning Electron Microscope SEM5000 can be used to observe the microstructure of ceramic materials and related products easily, and in addition, the X-ray energy spectrometer can be used to determine the elemental composition of materials quickly.    Application of SEM in the Study of Electronic CeramicsThe largest end-use market of the special ceramics industry is the electronics industry, where barium titanate (BaTiO3) is widely used in multilayer ceramic capacitors (MLCC), thermistors (PTC), and other electronic components because of its high dielectric constant, excellent ferroelectric and piezoelectric properties, and voltage resistance and insulation properties [2]. With the rapid development of the electronic information industry, the demand for barium titanate is increasing, and the electronic components are becoming smaller and more miniaturized, which also puts forward higher requirements for barium titanate.Researchers often regulate the properties by changing the sintering temperature, atmosphere, doping, and other preparation processes. Still, the essence is that the changes in the preparation process cause changes in the microstructure of the material and thus the properties. Studies have shown that the dielectric ferroelectric properties of barium titanate are closely related to the material's mi...

Metallic materials are materials with properties such as luster, ductility, easy conductivity, and heat transfer. They are generally classified into two types: ferrous and nonferrous metals. Ferrous metals include iron, chromium, manganese, etc. [1]. Among them, steel is the basic structural material and is called the "skeleton of industry". So far, steel still dominates the composition of industrial raw materials. Many steel companies and research institutes use the unique advantages of SEM to solve production problems and assist in the development of new products. SEM with corresponding accessories has become a favorite tool for the steel and metallurgical industry to conduct research and identify problems in the production process. With the increase in SEM resolution and automation, the application of SEM in material analysis and characterization is becoming more and more widespread [2].     Failure analysis is a new discipline that has been popularized by military enterprises to research scholars and enterprises in recent years [3]. Failure of metal parts can lead to degradation of workpiece performance in minor cases and even life safety accidents in major cases. Locating the causes of failure through failure analysis and proposing effective improvement measures is an essential step for ensuring the safe operation of the project. Therefore, making full use of the advantages of scanning electron microscopy will make a great contribution to the progress of the metallic materials industry.   01 SEM Observation of the Tensile Fracture of Metals   Fracture always occurs at the weakest point in the metal tissue and records much valuable information about the whole process of fracture. Therefore, the observation and study of fracture have been emphasized in the study of fracture. The morphological analysis of the fracture is used to study some basic problems that lead to the fracture of the material, such as the cause of fracture, the nature of the fracture, and the mode of fracture. If the fracture mechanism of the material is to be studied in depth, the composition of macro-areas on the fracture surface is usually analyzed. Fracture analysis has now become an important tool for failure analysis of metallic components.   Figure 1. CIQTEK SEM3100 Tensile Fracture Morphology   According to the nature of the fracture, the fracture can be roughly divided into brittle fracture and ductile fracture. The fracture surface of a brittle fracture is usually perpendicular to the tensile stress, and from the macroscopic point of view, the brittle fracture consists of a glossy crystalline bright surface; while the ductile fracture usually has a tiny bump on the fracture and is fibrous.   The experimental basis of fracture analysis is the direct observation and analysis of the fracture surface's macroscopic morphology and microstructural characteristics. In many cases, the nature of the fracture, the locatio...

Recently, global oil prices have risen sharply and the renewable energy industry represented by solar photovoltaic (PV) power generation has received widespread attention. As the core component of PV power generation, the development prospects and market values of solar PV cells are the focus of attention. In the global battery market, PV cells account for about 27%[1]. The scanning electron microscope plays a great role in enhancing the production process and related research of PV cells.     PV cell is a thin sheet of optoelectronic semiconductor that converts solar energy directly into electrical energy. The current commercial mass-produced PV cells are mainly silicon cells, which are divided into monocrystalline silicon cells, polycrystalline silicon cells and amorphous silicon cells.     Surface Texturing Methods for Solar Cell Efficiency Enhancement   In the actual production process of photovoltaic cells, in order to further improve the energy conversion efficiency, a special textured structure is usually made on the surface of the cell, and such cells are called "non-reflective" cells. Specifically, the textured structure on the surface of these solar cells improves the absorption of light by increasing the number of reflections of irradiated light on the surface of the silicon wafer, which not only reduces the reflectivity of the surface, but also creates light traps inside the cell, thus significantly increasing the conversion efficiency of solar cells, which is important for improving the efficiency and reducing the cost of existing silicon PV cells[2].     Comparison of Flat Surface and Pyramid Structure Surface Compared to a flat surface, a silicon wafer with a pyramidal structure has a higher probability that the reflected light from the incident light will act again on the surface of the wafer rather than reflecting directly back into the air, thus increasing the number of light scattered and reflected on the surface of the structure, allowing more photons to be absorbed and providing more electron-hole pairs.    Light Paths for Different Incident Angles of Light Striking the Pyramidal Structure   The commonly used methods for surface texturing include chemical etching, reactive ion etching, photolithography, and mechanical grooving. Among them, the chemical etching method is widely used in the industry because of its low cost, high productivity, and simple method[3]. For monocrystalline silicon PV  cells, the anisotropic etching produced by alkaline solution on different crystal layers of crystalline silicon is usually used to form a structure similar to the "pyramid" formation is the result of anisotropy of alkaline solution on different crystal layers of crystalline silicon. The formation of the pyramid structure is caused by the anisotropic reaction of alkali with silicon[4]. In a certain concentration of alkali solution, the reaction rate of OH- with the surface of Si...

Metallic materials are materials with properties such as luster, ductility, easy conductivity, and heat transfer. It is generally divided into two types: ferrous metals and non-ferrous metals. Ferrous metals include iron, chromium, manganese, etc. So far, iron and steel still dominate in the composition of industrial raw materials. Many steel companies and research institutes use the unique advantages of SEM to solve problems encountered in production and to assist in research and development of new products. Scanning electron microscopy with corresponding accessories has become a favorable tool for the steel and metallurgical industry to conduct research and identify problems in the production process. With the increase of SEM resolution and automation, the application of SEM in material analysis and characterization is becoming more and more widespread.   Failure analysis is a new discipline that has been popularized by military enterprises to research scholars and enterprises in recent years. Failure of metal parts can lead to degradation of workpiece performance in minor cases and life safety accidents in major cases. Locating the causes of failure through failure analysis and proposing effective improvement measures are essential steps to ensure safe operation of the project. Therefore, making full use of the advantages of scanning electron microscopy will make a great contribution to the progress of the metal material industry.     01 Electron microscope observation of tensile fracture of metal parts        Fracture always occurs in the weakest part of the metal tissue and records much valuable information about the whole process of fracture, so the observation and study of fracture has always been emphasized in the study of fracture. The morphological analysis of the fracture is used to study some basic problems that lead to the fracture of the material, such as the cause of fracture, the nature of fracture, and the mode of fracture. If we want to study the fracture mechanism of the material in depth, we usually have to analyze the composition of the micro-area on the surface of the fracture, and fracture analysis has now become an important tool for failure analysis of metal components.     Fig. 1 CIQTEK Scanning Electron Microscope SEM3100 tensile fracture morphology   According to the nature of fracture, the fracture can be broadly classified into brittle fracture and plastic fracture. The fracture surface of brittle fracture is usually perpendicular to the tensile stress, and the brittle fracture consists of glossy crystalline bright surface from the macroscopic view; the plastic fracture is usually fibrous with fine dimples on the fracture from the macroscopic view.   The experimental basis of fracture analysis is the direct observation and analysis of the macroscopic morphological and microstructural characteristics of the fracture surface. In many cases, the nature of the f...

Electron spin sensors have high sensitivity and can be widely used to probe various physicochemical properties, such as electric field, magnetic field, molecular or protein dynamics, and nuclear or other particles. These unique advantages and potential application scenarios make spin-based sensors a hot research direction at present. Sc3C2@C80 has a highly stable electron spin protected by a carbon cage, which is suitable for gas adsorption detection within porous materials. Py-COF is a recently emerged porous organic framework material with unique adsorption properties, which was prepared using a self-condensing building block with a formyl group and an amino group. prepared with a theoretical pore size of 1.38 nm. Thus, a metallofullerene Sc3C2@C80 unit (~0.8 nm in size) can enter one of the nanopores of Py-COF.   A nanospin sensor based on metal fullerene was developed by Taishan Wang, a researcher at the Institute of Chemistry, Chinese Academy of Sciences, for detecting gas adsorption within a porous organic framework. The paramagnetic metal fullerene, Sc3C2@C80, was embedded in the nanopores of a pyrene-based covalent organic framework (Py-COF). The adsorbed N2、CO、CH4、CO2、C3H6 and C3H8 within the Py-COF embedded with the Sc3C2@C80 spin probe were recorded using the EPR technique ( CIQTEK EPR200-Plus).It was shown that the EPR signals of the embedded Sc3C2@C80 regularly correlated with the gas adsorption properties of the Py-COF. The results of the study were published in Nature Communications under the title "Embedded nano spin sensor for in situ probing of gas adsorption inside porous organic frameworks".     Probing gas adsorption properties of Py-COF using molecular spin of Sc3C2@C8     In the study, the authors used a metallofullerene with paramagnetic properties, Sc3C2@C80 (~0.8 nm in size), as a spin probe embedded into one nanopore of pyrene-based COF (Py-COF) to detect gas adsorption within Py-COF. Then, the adsorption properties of Py-COF for N2、CO、CH4、CO2、C3H6 and C3H8 gases were investigated by recording the embedded Sc3C2@C80 EPR signals. It is shown that the EPR signals of Sc3C2@C80 regularly follow the gas adsorption properties of Py-COF. And unlike conventional adsorption isotherm measurements, this implantable nanospin sensor can detect gas adsorption and desorption by in situ real-time monitoring. The proposed nanospin sensor was also used to probe the gas adsorption properties of metal-organic framework (MOF-177), demonstrating its versatility.     Relationship between gas adsorption properties and EPR signals     Effect of gas pressure on EPR signal     EPR signal line width analysis   Spin-based sensors have attracted considerable attention owing to their high sensitivities. Herein, we developed a metallofullerene-based nano spin sensor to probe gas adsorption within porous organic frameworks. For this, spin-...