§ Longcheng Zhang and Jie Liang contributed equally to this work. Benzoate anions-intercalated NiFe-LDH nanosheet on carbon cloth (BZ-NiFe-LDH/CC) behaves as a highly efficient and durable electrocatalyst for alkaline seawater oxidation. In alkaline seawater, it attains the current density of 500 mA cm -2 at a low overpotential of 610 mV for 100-h uninterrupted electrolysis with no obvious structural change, reflecting significantly boosted activity and resistance toward chlorine species corrosion.

NH serves as an attractive hydrogen storage medium and a renewable energy sector for a sustainable future. Electrochemical reduction is a feasible ambient reaction to convert N to NH, while it needs efficient electrocatalysts for the N reduction reaction (NRR) to meet the challenge associated with N activation. In this Letter, we report on our recent experimental finding that the TiO nanosheets array on the Ti plate (TiO/Ti) is effective for electrochemical N conversion to NH at ambient conditions. When tested in 0.1 M NaSO, such TiO/Ti attains a high NH yield of 9.16 × 10 mol s·cm with corresponding Faradaic efficiency of 2.50% at -0.7 V vs reversible hydrogen electrode, outperforming most reported aqueous-based NRR electrocatalysts. It also shows excellent selectivity for NH formation with high electrochemical stability. The superior NRR activity is due to the enhanced adsorption and activation of N by oxygen vacancies in situ generated during electrochemical tests.

The sodium storage mechanism of hard carbon, optimization strategies of electrochemical performance, and the scientific challenges towards the commercialization of sodium-ion batteries were systematically summarized and analyzed.

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Na-doped Ni-rich LiNi0.5Co0.2Mn0.3O2 cathode material, Li0.97Na0.03Ni0.5Co0.2Mn0.3O2, is synthesized by a hydroxide co-precipitation route. The structural characterization reveals that the substitution of Na for Li results in a more ordered α-NaFeO2 structure, enlarges Li layer spacing, and reduces the degree of cation mixing. The Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 material has a high tap density of 2.17 g cm(-3) that meets the commercial requirement in lithium ion batteries (LIBs). The galvanostatic charge/discharge results show that the electrochemical performance of the Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 is significantly improved. At 0.2, 1, 10, 30 and 50 C, the specific capacities of the Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 are 228.43, 163.12, 121.43, 95.56 and 60.09 mA h g(-1), respectively, which are superior to those of the undoped LiNi0.5Co0.2Mn0.3O2 due to the enlargement of Li layer spacing, the decreased degree of cation mixing, and the rapid diffusion of Li-ion in the bulk lattice after the substitution of Na for Li. Therefore, the Na-doped Ni-rich LiNi0.5Co0.2Mn0.3O2 material is a promising cathode candidate for the next generation of LIBs.

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The Na+ superionic conductor (NASICON)‐type Na3V2(PO4)3 cathodes have attracted extensive interest due to their high structural stability and fast Na+ mobility. However, the substitution of vanadium with low‐cost active elements remains imperative due to high cost of vanadium, to further boost its application feasibility. Herein, a novel ternary NASICON‐type Na4VMn0.5Fe0.5(PO4)3/C cathode is designed, which integrates the advantages of large reversible capacity, high voltage, and good stability. The as‐obtained Na4VMn0.5Fe0.5(PO4)3/C composite can deliver an excellent rate capacity of 96 m Ah g‐1 at 20 C and decent cycling durability of 94% after 3000 cycles at 20 C, which is superior to that of Na4VFe(PO4)3/C and Na4VMn(PO4)3/C. The synergetic contributions of multimetal ions and facilitated Na+ migration of the Na4VMn0.5Fe0.5(PO4)3/C cathode are confirmed by the first‐principles calculations. The processive reduction/oxidation involved in Fe2+/Fe3+, Mn2+/Mn3+, V3+/V4+/V5+ redox couples are also revealed upon the charging/discharging process by ex situ soft X‐ray absorption spectroscopy. The reversible structure evolution and small volume change during the electrochemical reaction is demonstrated by in situ X‐ray diffraction characterization. The rational design of NASICON‐type cathodes by regulating composition with substitution of multimetal ions can provide new perspectives for high‐performance Na‐ion batteries.