Due to an ultrahigh theoretical specific capacity of 3860 mAh g−1, lithium (Li) is regarded as the ultimate anode for high‐energy‐density batteries. However, the practical application of Li metal anode is hindered by safety concerns and low Coulombic efficiency both of which are resulted fromunavoidable dendrite growth during electrodeposition. This study focuses on a critical parameter for electrodeposition, the exchange current density, which has attracted only little attention in research on Li metal batteries. A phase‐field model is presented to show the effect of exchange current density on electrodeposition behavior of Li. The results show that a uniform distribution of cathodic current density, hence uniform electrodeposition, on electrode is obtained with lower exchange current density. Furthermore, it is demonstrated that lower exchange current density contributes to form a larger critical radius of nucleation in the initial electrocrystallization that results in a dense deposition of Li, which is a foundation for improved Coulombic efficiency and dendrite‐free morphology. The findings not only pave the way to practical rechargeable Li metal batteries but can also be translated to the design of stable metal anodes, e.g., for sodium (Na), magnesium (Mg), and zinc (Zn) batteries.

A double-wrapped binder has been rationally designed with high Young's modulus polyacrylic acid (PAA) inside and low Young's modulus bifunctional polyurethane (BFPU) outside to address the large inner stress of silicon anode with drastic volume changes during cycling. Harnessing the "hard to soft" gradient distribution strategy, the rigid PAA acts as a protective layer to dissipate the inner stress first during lithiation, while the elastic binder BFPU serves as a buffer layer to disperse residual stress, and thus avoids structural damage of rigid PAA. Moreover, the introduction of BFPU with fast self-healing ability can dynamically recover the microcracks arising from large stress, further ensuring the integrity of silicon anode. This multifunctional binder with smart design of double-wrapped structure provides enlightenment on enlarging the cycling life of high-energy-density lithium-ion batteries that suffer enormous volume change during the cycling process.

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A segment of Mesozoic subduction-accretion zone was inferred across the northeastern South China Sea at approximately NE45° orientation. Basic evidence includes the following: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in size and intensity to that of the Manila subduction-accretion zone. A belt of high positive magnetic anomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arc associated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and present seafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally by NW-running strike-slip faults, in concord with the Mesozoic stress field of South China. In addition, the existence of the subduction zone is supported by wide-angle seismic data obtained in different years by different institutions. At approximate localities, a north-dipping ramp of Moho surface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 km beneath the Moho reflector is indicated by both OBS and long-cable seismic records. The identification of a segment of Mesozoic subduction zone in NE South China Sea fills nicely the gap of the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra, Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

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Lithium metal is considered to be a promising anode material for high‐energy‐density rechargeable batteries because of its high theoretical capacity and low reduction potential. Nevertheless, the practical application of Li anodes is challenged by poor cyclic performance and potential safety hazards, which are attributed to non‐uniform electrodeposition of Li metal during charging. Herein, diffusion limited current density (DLCD), one of the critical fundamental parameters that govern the electrochemical reaction process, is investigated as the threshold of current density for electrodeposition of Li. The visualization of the concentration field and distribution of Faradic current density reveal how uniform electrodeposition of Li metal anodes can be obtained when the applied current density is below the DLCD of the related electrochemical system. Moreover, the electrodeposition of Li metal within broken solid electrolyte interphases preferentially occurs at the crack spots that are caused by the non‐uniform electrodeposition of Li metal. This post‐electrodeposition leads to more consumption of active Li when the applied current density is greater than the DLCD. Therefore, lowering the applied current density or increasing the DLCD are proposed as directions for developing advanced strategies to realize uniform electrodeposition of Li metal and stable interfaces, aiming to accelerate the practical application of state‐of‐the‐art Li metal batteries.

A variety of atomically dispersed transition-metal-anchored nitrogen-doped carbon (M−N−C) electrocatalysts have shown encouraging electrochemical CO 2 reduction reaction (CO 2 RR) performance, with the underlying fundamentals of central transition-metal atom determined CO 2 RR activity and selectivity yet remaining unclear. Herein, a universal impregnation-acid leaching method was exploited to synthesize various M− N−C (M: Fe, Co, Ni, and Cu) single-atom catalysts (SACs), which revealed d-orbital electronic configuration-dependent activity and selectivity toward CO 2 RR for CO production. Notably, Ni−N−C exhibits a very high CO Faradaic efficiency (FE) of 97% at −0.65 V versus RHE and above 90% CO selectivity in the potential range from −0.5 to −0.9 V versus RHE, much superior to other M−N−C (M: Fe, Co, and Cu). With the d-orbital electronic configurations of central metals in M−N−C SACs well elucidated by crystal-field theory, Dewar−Chatt−Duncanson (DCD) and differential charge density analysis reveal that the vacant outermost dorbital of Ni 2+ in a Ni−N−C SAC would benefit the electron transfer from the C atoms in CO 2 molecules to the Ni atoms and thuseffectively activate the surface-adsorbed CO 2 molecules. However, the outermost d-orbital of Fe 3+ , Co 2+ , and Cu 2+ occupied by unpaired electrons would weaken the electron-transfer process and then impede CO 2 activation. In situ spectral investigations demonstrate that the generation of *COOH intermediates is favored over Ni−N−C SAC at relatively low applied potentials, supporting its high CO 2 -to-CO conversion performance. Gibbs free energy difference analysis in the rate-limiting step in CO 2 RR and hydrogen evolution reaction (HER) reveals that CO 2 RR is thermodynamically favored for Ni−N−C SAC, explaining its superior CO 2 RR performance as compared to other SACs. This work presents a facile and general strategy to effectively modulate the CO 2to-CO selectivity from the perspective of electronic configuration of central metals in M−N−C SACs.