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The advancement of K metal anodes has long been hindered by challenges including dendrite proliferation and volume expansion amid electrochemical cycles. Generic interlayer design for extended anodes and its K uptake/release mechanism remain unexplored to date. Herein, a generic alloy‐boosted strategy is reported to devise a ZnX‐loaded (X = S, Se or Te) porous carbon nanofiber (PCNF) membrane as an efficient 3D interphase layer for K metal anodes. Theoretical computations and experimental investigations suggest that representative ZnTe acts as an alloying site, thereby reducing the nucleation energy barrier and optimizing the deposition pattern of K. Such a maneuver enables dendrite‐free plating of K metal within the interface layer, which facilitates the construction of an extended K anode. As a result, the symmetric cell modified with ZnTe@PCNF demonstrates a lifespan of over 3100 h. When coupled with a cathode, the full cell delivers a capacity retention of 94% after 500 cycles at 1.0 A g⁻¹, showing its potential for the development of practically viable K metal batteries. [ABSTRACT FROM AUTHOR]

Calcium‐ion batteries are emerging as a promising alternative to lithium‐ion batteries by offering potential advantages in cost, affordability, and safety. However, the development of high‐performance calcium batteries has been hindered by the lack of high‐capacity cathodes. Here a small molecular organic cathode, 9,10‐phenanthrenequinone (PQ), is reported which leverages the rapid enolization chemistry of multi‐redox centers (C═O) and the flexible intermolecular structure for high performance. The PQ cathode demonstrates an impressive specific capacity of 250 mAh g−1 at 0.2 C for 200 cycles and superior rate capabilities. The robust performance of PQ cathodes is attributed to the mitigation of small molecule electrode dissolution in the weakly solvating ether electrolytes and the promotion of inter‐and intralayer Ca ion diffusion pathways, which synergistically facilitate the retention of high capacities at elevated current rates. When paired with a Ca metal anode, the full cell achieves remarkable capacities of 214 mAh g−1 at 0.2 C, with an average operating voltage of 2.5 V versus Ca/Ca2+, representing the highest performance among CMBs reported to date. The use of organic cathodes in tailored electrolytes with restricted intermediate dissolutions heralds a new era in the development of multivalent metal batteries. [ABSTRACT FROM AUTHOR]

Potassium‐ion hybrid capacitors (KICs) reconciling the advantages of batteries and supercapacitors have stimulated growing attention for practical energy storage because of the high abundance and low cost of potassium sources. Nevertheless, daunting challenge remains for developing high‐performance potassium accommodation materials due to the large radius of potassium ions. Molybdenum diselenide (MoSe2) has recently been recognized as a promising anode material for potassium‐ion batteries, achieving high capacity and favorable cycling stability. However, KICs based on MoSe2 are scarcely demonstrated by far. Herein, a diatomite‐templated synthetic strategy is devised to fabricate nitrogen‐doped MoSe2/graphene (N‐MoSe2/G) composites with favorable pseudocapacitive potassium storage targeting a superior anode material for KICs. Benefiting from the unique biomorphic structure, high electron/K‐ion conductivity, enriched active sites, and the conspicuous pseudocapacitive effect of N‐MoSe2/G, thus‐derived KIC full‐cell manifests high energy/power densities (maximum 119 Wh kg−1/7212 W kg−1), outperforming those of recently reported KIC counterparts. Furthermore, the potassium storage mechanism of N‐MoSe2/G composite is systematically explored with the aid of first‐principles calculations in combination of in situ X‐ray diffraction and ex situ Raman spectroscopy/transmission electron microscopy/X‐ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

Potassium metal batteries (KMBs) hold promise for stationary energy storage with certain cost and resource merits. Nevertheless, their practicability is greatly handicapped by dendrite-related anodes, and the target design of specialized separators to boost anode safety is in its nascent stage. Here, we develop a thermally robust biopolymeric separator customized via a solvent-exchange and amino-siloxane decoration strategy to render durable and safe KMBs. Through experimental investigation and theoretical computation, we reveal that the optimized porosity and surface functionalization could manage ion transport and interfacial chemistry, thereby enabling efficient K + diffusion and a favorable solid electrolyte interphase to achieve prolonged cycling stability (over 3000 h). The thus-assembled full cell retains 80% of its initial capacity after 400 cycles at 0.5 A g -1 . The heat-proof property of the designed separator is further demonstrated. Our biopolymeric separator, affording multifunctional features, provides an appealing solution to circumvent instability and safety issues associated with potassium metal batteries.

Objective: To establish the HPLC chromatographic fingerprint of Kumu injection and to simultaneously determine the contents of three beta-carboline alkaloids, comprehensively evaluating the immanent quality of Kumu injection., Method: The chromatographic analysis was performed on a Phenomenex Gemini C18 ( 4.6 mm x 250 mm, 5 microm) column with the gradient elution solvent system composed of methanol and 30 mmol x L(-1) aqueous ammonium acetate (adjusted with glacial acetic acid to pH 4.5). Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004 A) was used in data analysis., Result: Sixteen co-possessing peaks were selected as the fingerprints of Kumu injection, and 7 peaks were identified by chemical reference substances. There were good similarities between the standard fingerprint chromatogram and each fingerprint chromatogram from the eleven samples for their similarity coefficients were not less than 0.9. Three kinds of beta-carboline alkaloids were separated well. The correlation coefficients were 0.999 9. The linear ranges of three components were 0.020 0-0.300 0, 0.102 0-1.530 0, 0.015 2-0. 228 0 microg, respectively, and the average recoveries ranged were from 99.5% to 102%., Conclusion: The method of fingerprint combined with quantitative analysis is sensitive, selective, and provide scientific basis for quality control of Kumu Injection.