Using molecularly imprinted polymer to recognize various target molecules emerges as a fascinating research field. Herein, we applied this strategy for the first time to efficiently recognize and trap long-chain polysulfides (LiS, x = 6-8) in lithium sulfur battery to minimize the polysulfide shuttling between anode and cathode, which enables us to achieve remarkable electrochemical performance including a high specific capacity of 1262 mAh g at 0.2 C and superior capacity retention of over 82.5% after 400 cycles at 1 C. The outstanding performance is attributed to the significantly reduced concentration of long-chain polysulfides in electrolyte as evidenced by in situ UV/vis spectroscopy and LiS nucleation tests, which were further confirmed by density functional theory calculations. The molecular imprinting is demonstrated as a promising approach to effectively prevent the free diffusion of long-chain polysulfides, providing a new avenue to efficiently recognize and trap lithium polysulfides for high-performance lithium sulfur battery with greatly suppressed shuttle effect.

The heteroatom co-doped carbonaceous anodes have readily attracted great attention in potassium-ion batteries (PIBs), owing to their augmented carbon interlayer distances and increased K + storage sites to induce enhanced capacity value. Nevertheless, the synergistic effect of dual-doped heteroatoms is still unclear and lacks systematic explorations. In addition, traditional synthetic routes are cumbersome with template removal step, which are normally deficient in product scalability. Herein, a generic protic-salt strategy is devised to realize sulfur-, phosphorus-or boron-nitrogen dual-doped carbon (SNC, PNC, or BNC) via varying the types of protic precursors (e.g., the acid). Throughout comprehensive instrumental probing and theoretical simulation, it is identified that the presence of B-N moiety can harvest high adsorption capability of K + and hence exhibit more obvious pseudocapacitance behavior than bare N-doped carbon counterpart. As a PIB anode, the BNC electrode displays an impressive reversible capacity (360.5 mAh g −1 at 0.1 A g −1 ) and cycle stability (125.4 mAh g −1 at 1 A g −1 after 3000 cycles). In situ/ex situ characterizations further reveal the origin of the excellent electrochemical properties of the BNC electrode. Such a tailorable protic-salt derived anode material offers new possibilities to advance PIB devices.

Sn4P3 binary alloy anode has attracted much attention, not only because of the synergistic effect of P and Sn, but also its universal popularity in alkali metal ion batteries (AIBs), including lithium‐ion batteries (LIBs), sodium‐ion batteries (SIBs), and potassium‐ion batteries (PIBs). However, the alkali metal ion (A+) storage and capacity attenuation mechanism of Sn4P3 anodes in AIBs are not well understood. Herein, a combination of ex situ X‐ray diffraction, transmission electron microscopy, and density functional theory calculations reveals that the Sn4P3 anode undergoes segregation of Sn and P, followed by the intercalation of A+ in P and then in Sn. In addition, differential electrochemical curves and ex situ XPS results demonstrate that the deep insertion of A+ in P and Sn, especially in P, contributes to the reduction in capacity of AIBs. Serious sodium metal dendrite growth causes further reduction in the capacity of SIBs, while in PIBs it is the unstable solid electrolyte interphase and sluggish dynamics that lead to capacity decay. Not only the failure mechanism, including structural deterioration, unstable SEI, dendrite growth, and sluggish kinetics, but also the modification strategy and systematic analysis method provide theoretical guidance for the development of other alloy‐based anode materials.

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Using first-principles density functional theory calculations, we investigate the energetics and electronic properties of Stone Wales and vacancy defects in blue phosphorene. Among these defects, the Stone Wales defect has the lowest formation energy of 1.49 eV. Single and double vacancy defects have much larger formation energies (2.35∼2.90 eV). All the defects induce mid-gap bands that are relatively flat, which indicates the localized nature of the defect states. Our spin-polarized calculations further show that a single vacancy defect exhibits local magnetic moments (1.0 μ B ), which can be attributed to the existence of an unpaired electron. Besides, we propose new types of defects with irregular buckling configurations. These new defects have even lower formation energies (1.01 and 1.30 eV). The present work may serve as an important guidance for designing and defect engineering of blue phosphorene-based devices.