Ac ompetitive complexation strategy has been developed to construct an ovel electrocatalyst with Zn-Co atomic pairs coordinated on Nd oped carbon support (Zn/ CoN-C). Sucha rchitecture offers enhanced binding ability of O 2 ,s ignificantly elongates the O À Ol ength (from 1.23 to 1.42 ), and thus facilitates the cleavage of O À Ob ond, showing at heoretical overpotential of 0.335 Vd uring ORR process.A saresult, the Zn/CoN-C catalyst exhibits outstanding ORR performance in both alkaline and acid conditions with ah alf-wave potential of 0.861 and 0.796 Vr espectively. The in situ XANES analysis suggests Co as the active center during the ORR. The assembled zinc-air battery with Zn/CoN-Ca sc athode catalyst presents am aximum power density of 230 mW cm À2 along with excellent operation durability.T he excellent catalytic activity in acid is also verified by H 2 /O 2 fuel cell tests (peak power density of 705 mW cm À2 ).

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Li-Se, [8] and that have extremely high energy densities. However, the nonuniform deposition of Li ions (Li + ) and the large volume change of the Li-metal anode during cycling result in the formation of numerous cracks in the solid-electrolyte interface (SEI) layers, [10][11][12] which accelerate the inhomogeneous deposition of Li and consume more electrolyte, [12,13] causing significant safety issues and low Coulombic efficiency (CE). [14][15][16] In order to solve these problems, tremendous efforts have been made to achieve uniform Li deposition or a steady SEI passivation layer by modifying the solid-state electrolyte, [3,[17][18][19] using lithiophilic hosts, [20][21][22][23][24] and adding electrolyte additives. [25][26][27] Another critical issue is the effect of current density on Li deposition behavior. [28,29] Compared with planar electrodes, a 3D current collector effectively reduces the local current density and delays Li dendrite growth rate due to a larger specific surface area. [30][31][32][33][34] However, there is a

A competitive complexation strategy has been developed to construct a novel electrocatalyst with Zn‐Co atomic pairs coordinated on N doped carbon support (Zn/CoN‐C). Such architecture offers enhanced binding ability of O2, significantly elongates the O−O length (from 1.23 Å to 1.42 Å), and thus facilitates the cleavage of O−O bond, showing a theoretical overpotential of 0.335 V during ORR process. As a result, the Zn/CoN‐C catalyst exhibits outstanding ORR performance in both alkaline and acid conditions with a half‐wave potential of 0.861 and 0.796 V respectively. The in situ XANES analysis suggests Co as the active center during the ORR. The assembled zinc–air battery with Zn/CoN‐C as cathode catalyst presents a maximum power density of 230 mW cm−2 along with excellent operation durability. The excellent catalytic activity in acid is also verified by H2/O2 fuel cell tests (peak power density of 705 mW cm−2).

The serious safety issues caused by uncontrollable lithium (Li) dendrite growth, especially at high current densities, seriously hamper the rapid charging of Li metal‐based batteries. Here, the construction of Al–Li alloy/LiCl‐based Li anode (ALA/Li anode) is reported by displacement and alloying reaction between an AlCl3‐ionic liquid and a Li foil. This layer not only has high ion‐conductivity and good electron resistivity but also much improved mechanical strength (776 MPa) as well as good flexibility compared to a common solid electrolyte interphase layer (585 MPa). The high mechanical strength of the Al–Li alloy interlayer effectively eliminates volume expansion and dendrite growth in Li metal batteries, so that the ALA/Li anode achieves superior cycling for 1600 h (2.0 mA cm−2) and 1000 cycles at an ultrahigh current density (20 mA cm−2) without dendrite formation in symmetric batteries. In lithium–sulfur batteries, the dense alloy layer prevents direct contact between polysulfides and Li metal, inhibiting the shuttle effect and electrolyte decomposition. Long cycling performance is achieved even at a high current density (4 C) and a low electrolyte/sulfur (6.0 µL mg−1). This easy fabrication process provides a strategy to realize reliable safety during the rapid charging of Li‐metal batteries.

Changing the solvation sheath of hydrated Zn ions is an effective strategy to stabilize Zn anodes to obtain a practical aqueous Zn‐ion battery. However, key points related to the rational design remain unclear including how the properties of the solvent molecules intrinsically regulate the solvated structure of the Zn ions. This study proposes the use of a stability constant (K), namely, the equilibrium constant of the complexation reaction, as a universal standard to make an accurate selection of ligands in the electrolyte to improve the anode stability. It is found that K greatly impacts the corrosion current density and nucleation overpotential. Following this, ethylene diamine tetraacetic acid with a superhigh K effectively suppresses Zn corrosion and induces uniform Zn‐ion deposition. As a result, the anode has an excellent stability of over 3000 h. This work presents a general principle to stabilize anodes by regulating the solvation chemistry, guiding the development of novel electrolytes for sustainable aqueous batteries.

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The sodium (Na)-metal batteries hold great promise as a sustainable technology owing to the high element abundance and low cost. However, the generally used carbonate electrolytes remain highly reactive towards Na metal, leading to flammable gas evolution.Here, we propose an electrolyte sieving strategy to separate anion-mediated ion-pairs from dilute electrolytes by introducing a 3A zeolite molecular sieve film. The anion-mediated ion-pair firstly weakens the electron-withdrawing property of the cation, which effectively suppresses the gassing. In addition, the sieved electrolyte promotes the formation of robust inorganicdominated solid electrolyte interphases. Therefore, it contributes to stable Na plating/stripping in Na j Al half cells with Coulombic efficiency maintaining at 98.5 % and a long service life of 800 cycles in full cells. Moreover, the electrode stability is well preserved even under harsh conditions of high temperature and ester-based electrolytes with higher reactivity.