No abstract

Prussian blue analogues (PBAs) are considered one of the promising cathodes for sodium-ion batteries because of their low cost and tunable structure. As an intrinsic characteristic, the influence of structured water in PBAs on the electrochemical properties is still controversial. Herein, low-vacancy iron hexacyanoferrate with different interstitial water contents is synthesized through the citric acid-assisted single iron source method. Ex situ Fourier transform infrared and X-ray diffraction characterization reveals that the interstitial water can stably exist in the Prussian blue framework during repeated cycling. The longstanding interstitial water can reduce the volume change during the Na + insertion/extraction process, resulting in improved cycling stability. Thanks to the low Fe(CN) 6 4− vacancies and pillar role of interstitial water in the crystal framework, the HW-PB exhibits a high reversible capacity of 117 mAh g −1 and excellent long cycle performance with a capacity retention of 91% after 1380 cycles. This work broadens the understanding of the relationship between the interstitial water in PBAs and Na-storage performances, providing guidance for the precise synthesis of high-quality PBAs.

The practical application of infancy‐stage rocking‐chair Zn‐ion batteries is predominately retarded by the strong electrostatic interaction between traditional anode materials with bivalent Zn2+, resulting in irreversible serious structural damage, unsatisfactory cycling stabilities, and poor rate performances. Herein, an advanced dual electric field in situ induced intercalation/conversion dual‐mechanism Na1.6TiS2/CuSe2 heterointerface anode towards ultrastable aqueous rocking‐chair zinc‐ion batteries is successfully constructed. The rational constructions of huge heterointerfaces between different phases generate built‐in electric fields, reducing the energy barrier for ion migration, facilitating electron/ion diffusion, decreasing charge transfer resistances, and establishing an excellent conducting network. The enhanced interactions of different atoms at the phase interface alleviate the tensile strain and stabilize the lattice, achieving superior Zn2+ diffusion kinetics. The dual‐mechanism Na1.6TiS2/CuSe2 heterostructures can reach a discharge capacity of 142 mAh g−1 at 0.2 A g−1. It still reaches a discharge capacity of 133 mAh g−1 when the current density recovers to 0.2 A g−1 after a high current evaluation of 10 A g−1 with remarkable capacity retention (83.8% at 5A g−1 after 12 000 cycles). This breakthrough opens a new avenue for the targeted design of rocking‐chair zinc‐ion batteries and provides insights into the evolution of heterointerfaces.

The major findings of the present study in human subjects undergoing elective cardiac operations with cardiopulmonary bypass are as follows: (1) bypass was associated with an up-regulation of the adhesion molecules L-selectin, CD11b, and CD11c but with no significant change in CD11a expression, and (2) the clinical use of a leukocyte-depleting filter could down-regulate the expression of CD11b and L-selectin.