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Manganese dioxide with high theoretical capacity has drawn a great deal of attention for aqueous zinc‐ion batteries (ZIBs). Nevertheless, their sluggish diffusion kinetics, low electrical conductivity and limited active sites are still hindering the potential application in batteries. Herein, amorphous MnO2 nanosheets with abundant oxygen vacancies are facilely prepared by using carboxymethylcellulose sodium (CMC) as a capping agent. During the growth process, CMC can preferentially attach to the (003) facet of MnO2 to guide its crystal growth and morphology. The small nanosheets can expose abundant edge sites, along with the surface oxygen vacancies, to facilitate the insertion/extraction of H+ and Zn2+ in ZIBs. Moreover, the presence of CMC can stabilize the Mn3+ to inhibit the Jahn–Teller effect in the preparation process. As a result, CMC‐MnO2 based ZIB can provide a specific capacity of 324 mAh g−1 at 0.5 A g−1, and achieve 86.2% retention after a long cycle test of 1000 cycles. Furthermore, the energy storage mechanism may be attributed to the insertion/extraction of H+/Zn2+, dissolution/deposition of MnO2 and Zn4SO4(OH)6·nH2O, and irreversible transformation of vermiculite during long cycles. This work may open new perspectives for the development of MnO2‐based cathodes in ZIBs. [ABSTRACT FROM AUTHOR]

Sulfide solid‐state electrolytes (SSEs) with superior ionic conductivity and processability are highly promising candidates for constructing all‐solid‐state lithium metal batteries (ASSLMBs). However, their practical applications are limited by their intrinsic air instability and serious interfacial incompatibility. Herein, a novel glass‐ceramic electrolyte Li3.12P0.94Bi0.06S3.91I0.18 was synthesized by co‐doping Li3PS4 with Bi and I for high‐performance ASSLMBs. Owing to the strong Bi‒S bonds that are thermodynamically stable to water, increased unit cell volume and Li+ concentration caused by P5+ substitution with Bi3+, and the in situ formed robust solid electrolyte interphase layer LiI at lithium surface, the as‐prepared Li3.12P0.94Bi0.06S3.91I0.18 SSE achieved excellent air stability with a H2S concentration of only 0.205 cm3 g−1 (after 300 min of air exposure), outperforming Li3PS4 (0.632 cm3 g−1) and the most reported sulfide SSEs, together with high ionic conductivity of 4.05 mS cm−1. Furthermore, the Li3.12P0.94Bi0.06S3.91I0.18 effectively improved lithium metal stability. With this SSE, an ultralong cyclability of 700 h at 0.1 mA cm−2 was realized in a lithium symmetrical cell. Moreover, the Li3.12P0.94Bi0.06S3.91I0.18‐based ASSLMBs with LiNi0.8Mn0.1Co0.1O2 cathode achieved ultrastable capacity retention rate of 95.8% after 300 cycles at 0.1 C. This work provides reliable strategy for designing advanced sulfide SSEs for commercial applications in ASSLMBs. [ABSTRACT FROM AUTHOR]

Solid‐state sodium metal batteries (SSMBs) possess superior safety and high energy density over liquid counterparts, and therefore hold great promise for large‐scale energy storage application. In this review, the recent development of the advanced sodium‐based solid‐state electrolytes (SSEs) for high‐performance SSMBs is systematically summarized. First, the fundamental mechanisms and key parameters of SSEs, including ionic conductivity, electrochemical stability and Na+ transference number, are introduced in details, and then various inorganic (Na‐β‐alumina, Na superionic conductors, and sulfides), polymer SSEs (solid polymer SSEs and gel polymer SSEs), and inorganic‐polymer hybrid SSEs are elaborately discussed, emphasizing the unique roles of structure optimization and interface engineering of SSEs for boosting electrochemical performance in SSMBs. Finally, the key challenges and promising prospects of advanced SSEs in terms of interface optimization of inorganic SSEs, molecular design and screening of polymer SSEs, objective evaluation, and multiscale characterizations of SSEs are briefly proposed. [ABSTRACT FROM AUTHOR]

At present, China's football sports are relatively backward in training theory and practice. If you want to break out of Asia and enter the world, and gain a firm foothold in the international football arena, you must use a scientific and realistic attitude, absorb the successful experience of advanced football countries, reflect on our training concepts and practices, and deeply study the training laws of football, in order to find a way suitable for our development. Athletes' competitive ability is the core issue of sports training. The failure of our football level is directly related to our systematic understanding of athletes' competitive ability. This problem has led to the separation of our training practice from the actual competition, making training unable to meet the needs of the competition. Only by solving this problem, can we improve the level of football in China. The football players' competitive ability evaluation is affirmed as multiple attribute decision making (MADM). In such paper, motivated by the idea of cotangent similarity measure (CSM), the CSMs are extended to DVNSs and four CSMs are created under DVNSs. Then, two weighted CSMs are built for MADM under DVNSs. Finally, a numerical example for Football players' competitive ability evaluation is affirmed and some comparative algorithms are produced to affirm the built method. [ABSTRACT FROM AUTHOR]