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To enrich the crystal growth strategies for the booming applications concerning lattice structure, a preferred facet‐growth method is proposed for solvothermal synthesis of target (BiO)2CO3 in the two‐phase system. The dominant crystal phase can be regulated from α‐Fe2O3 to (BiO)2CO3 by properly increasing dosage of Bi feedstock, and the optimized composite is composed of (BiO)2CO3 nanocrystal (≈10 nm) and amorphous iron oxide (defined as "FOB‐50"). Based on experimental characterizations and theoretical calculations, the highly matched lattice between (006)/(0012) facets of α‐Fe2O3 and {010} facet group of (BiO)2CO3 involving orientation of Fe─O─Fe bond and Bi─O─Bi bond is verified to facilitate the interaction between the above facets, resulting in preferred growth of {010} dominated by (040) facet in (BiO)2CO3 and its composites. The structural merits can not only enable the FOB‐50‐based electrodes to achieve a high capacity and unprecedentedly stable cyclic performances for 1500 cycles/a long time‐span of 32 months as anode materials, but also ensure the full‐cell to well inherit the electrochemical features of the cathode in potassium ion batteries (PIBs). This work can provide new insight into lattice regulation for bismuth‐based materials and expand their application as electrodes for high performance PIBs and lithium ion batteries. [ABSTRACT FROM AUTHOR]

A MnO@N-doped carbon (MnO@N-C) composite, with a three-dimensional (3D) ground-moss-like structure, was synthesized through hydrothermal treatment, polydopamine coating, and calcination, all without the use of surfactants. In lithium-ion batteries, the MnO@N-C sample, when used as an anode, achieved a performance of 563 mAh g−1 at 1.0 A g−1 across 300 cycles and boasted an initial Coulombic efficiency of 73.2%. In contrast, the MnO electrode had a discharge capacity of 258 mAh g−1 and an efficiency of 53.3% under the same conditions. The improved performance stems from the 3D carbon networks hosting MnO. These networks enhance MnO's electron transfer ability and offer space to offset volume changes during the charge–discharge cycle. [ABSTRACT FROM AUTHOR]

A rationally designed strategy was employed for the preparation of VN@C hollow structures using ZIF-8 polyhedra as sacrificial templates. Meanwhile, ZIF-8 also plays the role of both nitrogen and carbon sources during the synthetic process. Benefiting from the unique loose hollow structure with high surface area of VN@C, as well as the support of carbon, the product displays an outstanding lithium storage performance. The discharge capacity can reach 495.3 mA h g−1 at 1 A g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

Lithium metal is regarded as one of the most promising candidates for next-generation batteries. However, lithium dendrite formation and dead lithium accumulation are the critical problems which hinder its practical application. Herein, we constructed a flexible coating membrane layer which could effectively uniform the lithium deposition by isolating lithium metal from electrolyte and regulating the ion flux distribution. After modification, both the Li‖Li symmetric cells (more than 1,400 h at 1 mA·cm−2 and 1 mAh·cm−2) and Li‖Cu cells (more than 500 cycles at 0.5 mA·cm−2 and 0.5 mAh·cm−2, coulombic efficiency over 98%) deliver excellent long-cycle performance with high coulombic efficiency. The high performance is also proved in LiFePO4 (capacity retention increases from 79% to 93% at 2 C after 400 cycles) and NCM811 full cells (capacity retention from 28.5% to 78% at 2 C after 500 cycles). High electro-performance in batteries demonstrates that the multifunctional layer plays a crucial role in stabilizing lithium anode. Moreover, in order to verify the universality of the method, we have extended this facile way to fabricate other types of flexible membranes. This work offers an insight into solving the current obstacles in the application of lithium metal batteries. [ABSTRACT FROM AUTHOR]

Tin dioxide (SnO2) has been the focus of attention in recent years owing to its high theoretical capacity (1494 mAh g−1). However, the application of SnO2 has been greatly restricted because of the huge volume change during charge/discharge process and poor electrical conductivity. In this paper, a composite material composed of SnO2 and S, N co-doped carbon (SnO2@SNC) was prepared by a simple solid-state reaction. The as-prepared SnO2@SNC composite structures show enhanced lithium storage capacity as compared to pristine SnO2. Even after cycling for 1000 times, the as-synthesized SnO2@SNC can still deliver a discharge capacity of 600 mAh g−1 (current density: 2 A g−1). The improved electrochemical performance could be attributed to the enhanced electric conductivity of the electrode. The introduction of carbon could effectively improve the reversibility of the reaction, which will suppress the capacity fading resulting from the conversion process. [ABSTRACT FROM AUTHOR]

Potassium ion batteries (PIBs), as a promising next‐generation electrochemical energy storage device, have drawn great attention in recent years due to the low price and abundant reserves of potassium resource. However, the severe electrode pulverization caused by repeatedly insertion/extraction of large radius of K+ hinders their application. Herein a novel strategy is employed to fabricate hierarchical macroporous hybrid composite, ultrathin MoSe2 nanosheets vertical growth on three‐dimension nitrogen‐doped cross‐linked macroporous carbon (HM‐MoSe2/N−C), via a template route and subsequent selenization process to alleviate the volume expansion and structure pulverization of the electrode. The electrochemical results demonstrate that the HM‐MoSe2/N−C is a good anode for PIBs including high specific capacity (222.8 mA h g−1 at 0.1 A g−1), superior rate capability, and long‐term cycling stability (172.5 mA h g−1 at 0.5 A g−1 after 400 cycles). The extraordinary electrochemical performance of this HM‐MoSe2/N−C electrode is attributed to the elegant and adequate nanostructure design, which can offer abundant exposed active sites (ultrathin MoSe2 nanosheets), adequate volume accommodation (3D interconnected macropores), and highly conductive carbon frame with fast ion diffusion. [ABSTRACT FROM AUTHOR]