Collophanite fluorapatite particles were prepared as seed crystals with Ca²⁺ and F^- ions, which were used to deeply purify low-concentration soluble inorganic phosphorus in water. The effects of combined reactants, reactant concentration, solution pH value and coexisting ions on the removal efficiency of phosphorus in water were investigated. To characterize the properties and clarify the mechanism of collophanite to remove soluble phosphates in water, the samples before and after pickling and phosphorus removal were characterized by scanning electron microscopy, transmission electron microscopy, thermoanalysis and Fourier transform infrared spectroscopy. Collophanite fluorapatite with calcium and fluorine exhibits the maximum phosphorus removal performance. The addition of Ca²⁺ ions significantly enhances the phosphorus removal efficiency, and F^- ions with a low concentration have a slight effect on the phosphorus removal efficiency. Therefore, F^- ions can be replaced by Ca²⁺ ions. When the initial concentration of phosphorus is 2 mg/L, pH value is > 6, and Ca²⁺ ions concentration is > 30 mg/L, the residual phosphorus concentration after the treatment is lower than 0.05 mg/L, thus meeting the Class Ⅱ standard of environmental tuality of water resource.

Dielectric capacitors, which store electrical energy in the form of electrostatic field via dielectric polarization, can be used in pulsed power electronics, due to their high power density and ultrashort discharge time. However, the energy density of dielectric capacitors is relatively low (<2 J/cm³), which has limited their further development. Therefore, it is necessary to develop dielectric energy storage materials with high energy density. In this paper, the history and performance characteristics of dielectric energy storage materials will be briefly described, while the research progress of different dielectric energy storage materials will be summarized. Besides, some of the unsolved problems related to dielectric energy storage materials will be touched and the future development of this research topic will be forecasted.

Solid state lithium metal batteries have extremely high safety, due to the non-flammable and non-volatile characteristics, which makes it possible to use high energy density lithium metal as negative electrode. However, there are still several challenges in the industrialization of solid state lithium metal batteries, such as high interface impedance, poor solid electrolyte/electrode compatibility, low electrolyte ionic conductivity and narrow electrochemical window. Therefore, the development of flexible solid electrolytes with high performance has become an important research topic, in terms of accelerating the development of solid state lithium metal batteries. Here, the latest research progress of composite solid electrolytes in solid state lithium metal batteries and the interface problems and solutions of composite solid electrolyte matching electrode materials will be comprehensively described.

In recent years, rechargeable batteries based on multivalent cations (Al³⁺, Mg²⁺, Ca²⁺, Zn²⁺, etc.) have attracted extensive attention due to their high natural abundance, low cost and good chemical safety. In this review, some achievements and breakthrough progress in the study of multivalent ion batteries, both from home and abroad research teams were summarized. It is found that most researches are focused on the development of anode and cathode materials and the optimization of electrolyte components in aluminum-ion and magnesium-ion batteries. However, there are still some tricky problems to be solved in the rapid development of multivalent ion batteries, such as the structural instability of the cathode materials, the slow migration of ions, the passivation and dendrite problems of the anodes, and the corrosion of the electrolytes. Finally, the future perspective of multivalent ion batteries is prospected. In the later study, looking for multivalent ion battery model with high energy density is the main research direction, in which we could make some explorations and experiments on the modification to the cathode and anode structures to improve corresponding performance, as well as the optimization and matching of multicomponent electrolytes to obtain high-performance multivalent ion batteries.

Thermoelectric materials (TE), which enable the direct energy conversion between heat and electricity, have attracted global attention in both academic and industrial sections, due to their significant applications in power generation and refrigeration. In this review, the research background of thermoelectrics will be introduced first, while the recent progress on several widely studied thermoelectric materials will be overviewed according to their working temperatures. In particular, their crystal structure characteristics and performance optimization strategies will be highlighted. The difficulties and challenges faced in thermoelectric technology, in terms of materials development, device fabrication and R&D modes, will be discussed. Finally, the prospect and expectation for the further development of thermoelectrics will be put forward.

Organic-inorganic hybrid perovskites exhibit excellent optoelectronic properties, such as high absorption coefficients, long carrier diffusion lengths and lifetimes, low-temperature solution processibility and so on. The highest recorded power conversion efficiency (PCE) of perovskite solar cells (PSCs) has reached 25.5%, displaying huge potential for their commercialization. Here, the definition and classification of perovskite semiconductors are first summarized. Subsequently, strategies to enhance the PCE and stability, development of lead-free perovskite alternatives and recent advances in the fabrication of large area devices are highlighted. Last but not the least, the economic feasibility of PSCs and the future prospects for commercialization are also discussed, which could be used as a reference for the future study and development of PSCs.

As a new type of secondary ion battery, aqueous zinc-ion batteries (AZIBs) showed a promising application prospect in the field of large-scale energy storage, due to their low cost, high safety, environmental friendliness and high-power density. In this article, the research progress of AZIBs will be summarized from three aspects, including cathode materials, anode materials and electrolytes. Furthermore, the bottlenecks such as the short cycle life of batteries in this research area will be identified, while the respective possible solutions such as "single-phase reaction mechanism" will be proposed. Finally, an outlook on future research and development directions for AZIBs with high energy density, high safety and long cycle life will be offered as a conclusion.

A new type of graphite carbon nitride (g-C₃N₄)/kaolinite composites with abundant nitrogen vacancies was prepared by using a facile thermal reduction method. The composites were characterized by using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer(FTIR), UV-Vis absorption spectroscopy and X-ray photoelectron spectrometry (XPS). Bisphenol A (BPA) was used as the target pollutant to evaluate the catalytic activity of the composites through photocatalysis coupled with persulfate oxidation. It was observed that the degradation rate of NGK-10:1 was 9.98 and 5.72 times higher than those of g-C₃N₄ and nitrogen vacancies modified g-C₃N₄, respectively. On one hand, the large specific surface area and high porosity provided with more reactive site and hence promoted the adsorption capacity of pollutants on the composites. On the other hand, the formation of nitrogen vacancies acted as the photo-generated electron trap centers and thus inhibited the recombination of electron-hole pairs. In addition, there would be more electrons to activate PMS, thus promoting the formation of SO₄^•- and ·OH. Quenching experimental results showed that the non-radical pathway played the major role in the removal of BPA.

Systematic studying the relationship between microstructure and properties of clay mineral materials at the atomic and electronic scales has become an important trend. In this paper, the research progress in computational simulation of surface/interface of mineral materials is reviewed, covering three directions, i.e., interface recombination, surface modification and structural modification. The relevant contents about atomic and electronic micromechanisms are summarized, while the challenges and future development direction of mineral material functional design are prospected.

A tripolyphosphate-intercalated layered double hydroxide compound (LDH-P) was prepared by using exchange method, with flame retardant and structural characteristics. Then, sodium oleate was used to modify the hydroxide, thus forming LDH-P composite (LDH-P-S), by using a water bath method. The synergistic flame retardant behavior of the LDH-P-S with the combination of decabromodiphenyl ethane (DBDPE) on polypropylene (PP) was evaluated. When the content of LDH-P-S was 25% and the total loading of the flame regardant component was 30% in the system, the oxygen index of PP was increased from 24.2% to 24.9%, the total amount of smoke released was decreased by 10.3%, the peak heat release was decreased by 38%, and the vertical combustion performance reached V-0 level. Owing to the synergistic flame retardant effect of LDH-P-S and DBDPE, the amount of DBDPE could be reduced, while the comprehensive flame retardant performance could be effectively improved.