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Due to their good chemical and thermal stability, high heat of melting, and suitability within the desired temperature range, organic phase change materials (PCMs) are widely used for cooling electronic devices, new energy utilization, solar thermal power generation, industrial waste heat recovery processes, and greenhouse construction. However, the flammability of organic PCMs has limited their commercial viability. In recent years, researchers have been striving to improve the flame retardancy of organic PCMs through various strategies, raising the question of which modification strategy best enhances the flame retardancy for different types of composite PCMs. Therefore, a comprehensive and timely review is needed to gain insight into the mechanism of action for flame retardant properties enhancement. This article firstly introduces the types of flame retardants and flame retardant mechanism, and briefly introduces the test methods commonly used in the laboratory for the analysis of flame retardant mechanism. Secondly, the strategies for improving the flame retardancy of organic PCMs are systematically summarized, and some scenarios for the application of organic flame‐retardant PCMs are introduced. Eventually, the challenges and future perspectives of the evolution of organic flame retardant PCMs are presented. This review is expected to provide new insights for the rational design of high flame‐retardant organic PCMs. [ABSTRACT FROM AUTHOR]

Because of the high theoretical energy density of 2600 Wh kg -1 , lithium-sulfur batteries (LSBs) are anticipated to be among the next generation of high-energy-density storage technologies. However, the practical application of LSBs has been severely hampered by the significant shuttle effect and slow redox kinetics of polysulfides (LiPSs). To address the above problems, in this paper, the concept of quantum dots (QDs) was introduced to design and synthesize Mo 2 N QD-modified N-doped graphene nanosheets (marked as Mo 2 N-QDs@NG), which were used as separator modification materials for LSBs. The experimental results demonstrated that the introduction of Mo 2 N QDs avoids stacking of graphene sheets and provides more active sites for the conversion of LiPSs. Moreover, Mo 2 N enhances the chemical fixation and catalyzes the liquid-solid conversion of soluble LiPSs by forming Mo-S and Li-N bonds with LiPSs. Additionally, establishing Mo-C bonds with Mo 2 N, N-doped graphene sheets can facilitate the transport of electrons and ions and physically prevent the diffusion of LiPSs, thus creating a highly conducting carbon structure to support electrochemical reactions. Benefiting from the synergistic effect of chemical immobilization and catalysis of Mo 2 N QDs with the physical confinement of NG, Mo 2 N-QDs@NG-PP batteries exhibit enhanced electrochemical performance.