Abstract Incorporating electrocatalytic active sites into the reticular framework allows for the design of novel catalytic structures promoting desired catalytic reactions with efficient mass transfer. However, to fully exploit the advantages of such a framework, it is crucial to ensure the electrochemical stability of the material. In this context, alkaline‐stable bimetallic M x Ni 2‐x Cl 2 BTDD (M = Fe, Co) metal–organic frameworks (MOFs) are employed as electrocatalysts for alkaline water oxidation reaction (WOR) to understand the correlation between secondary metal incorporation and catalytic activity changes. For a specific Fe ratio within the MOF, the optimal catalytic activity is achieved at an overpotential of 315 mV at a WOR current density of 10 mA cm −2 geo . Based on its well‐defined crystal structure and uniformly arranged metal nodes, which are not limited to specific facets, the cooperative electrocatalytic mechanism during the faradaic WOR process is investigated through operando Raman spectroscopy and density functional theory calculations. These results enable the interpretation of the electrochemical WOR mechanism based on MOF, providing a further fundamental understanding of electrocatalytic activity in bimetallic systems.

Abstract Incorporating electrocatalytic active sites into the reticular framework allows for the design of novel catalytic structures promoting desired catalytic reactions with efficient mass transfer. However, to fully exploit the advantages of such a framework, it is crucial to ensure the electrochemical stability of the material. In this context, alkaline‐stable bimetallic M x Ni 2‐x Cl 2 BTDD (M = Fe, Co) metal–organic frameworks (MOFs) are employed as electrocatalysts for alkaline water oxidation reaction (WOR) to understand the correlation between secondary metal incorporation and catalytic activity changes. For a specific Fe ratio within the MOF, the optimal catalytic activity is achieved at an overpotential of 315 mV at a WOR current density of 10 mA cm −2 geo . Based on its well‐defined crystal structure and uniformly arranged metal nodes, which are not limited to specific facets, the cooperative electrocatalytic mechanism during the faradaic WOR process is investigated through operando Raman spectroscopy and density functional theory calculations. These results enable the interpretation of the electrochemical WOR mechanism based on MOF, providing a further fundamental understanding of electrocatalytic activity in bimetallic systems.

Lithium bis(fluorosulfonyl)imide (LiFSI) is widely used in lithium-metal batteries to form a stable lithium fluoride (LiF)-based solid electrolyte interphase (SEI). However, the FSI⁻ itself fails to create a protective passivation layer on aluminum (Al) current collectors, leading to Al³⁺ dissolution and severe corrosion. While fluorinated ether solvents have shown promise in mitigating Al corrosion, the mechanisms remain unclear. Here, the role of cation solvations and ion pairing structures is shown in corrosion mitigation. 2,2,3,3-tetrafluoro-1,4-dimethoxybutane (FDMB), a 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE)/1,2-dimethoxyethane (DME) mixture, and non-fluorinated ethers are evaluated in 1 m LiFSI. FDMB promoted the formation of AlF₃ while preventing corrosion under extreme conditions (e.g., 4.5 V vs Li/Li⁺, 60 °C). Electrochemical and DFT analyses showed that FDMB underwent favorable defluorination in coordination with both Li⁺ and Al³⁺ that arose from the oxidizing Al surface. Meanwhile, the formation of aggregated ion pairs between Li⁺ and FSI⁻ inhibited the generation of soluble Al³⁺ species coordinated with FSI^-. Modifying FDMB with alkyl chains further enhanced the anti-corrosive effects by reducing the solubility of Al³⁺ species. In contrast, DME/TTE exhibited more Al corrosion, similar to tetraethylene glycol dimethyl ether (TEGDME), due to less favorable defluorination by the limited solvation of Li⁺ and Al³⁺ on TTE.

A [Cu(NH 3 ) 4 ] 2+ complex, generated from dissolved Cu 2+ , not only promotes the electrochemical ammonia oxidation reaction (eAOR) over CuO electrocatalysts, but also forms dynamic cycles of dissolution and deposition via Cu 2+ ediated eAOR.

Concentrated cations are often employed to promote electrochemical CO₂ reduction reaction (CO₂RR) selectivity in acidic electrolytes. Here, we investigate the influence of excess cations on the *CO adsorption configuration and the product distribution of the CO₂RR. <i>Operando</i> attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) reveals that increasing the Cs⁺ concentration shifts the preference of the *CO intermediate on the Cu surface from the atop (*CO_atop) to the bridge (*CO_bridge) configuration. This transition leads to a sharp decline in C-C coupling and an increase in the hydrogen evolution reaction at high Cs⁺ concentrations (0.7 and 1.0 M) under acidic conditions. Time-resolved SEIRAS scans show that *CO_atop is kinetically dominant and the proportion of *CO_bridge increases gradually only at high cation concentrations. Density functional theory simulations confirm that Cs⁺ on the Cu surface can interact electrostatically with *CO and stabilize *CO_bridge over *CO_atop on the Cu surface. The evolution of *CO_bridge is also observed on Ag catalysts, indicating that the effect at high concentrations is not limited to Cu. Furthermore, polymeric binders on the Cu surface mitigate these detrimental effects on the CO₂RR and restore C₂H₄ production by preventing the cation from altering the *CO adsorption sites on the catalyst surface. This study provides new insights into the effects of cations on catalyst performance, with implications for catalyst design and operation.

Potassium (K) metal stands out as a promising anode material for rechargeable K batteries, due to its low redox potential and high capacity. However, K-metal anodes suffer from interfacial instability in polar organic electrolytes alongside uncontrolled dendrite growth during electrodeposition. Herein, we propose an innovative approach for improving the stability of K-metal anodes. This involves incorporating 4 wt % of 18-crown-6 (18C6) as an additive in a carbonate-based electrolyte solution comprising 0.5 M potassium hexafluorophosphate dissolved in ethylene carbonate/diethyl carbonate. The key of this strategy is that 18C6 coordinates K+ into the cavity, forming a robust K+–18C6 complex. This complex exhibits higher reductive stability compared to other ion–solvent complexes in the electrolyte. During the plating reaction, this unique feature induces an electrostatic shielding effect, altering the transition of the K-deposition behavior from self-amplification to self-flattening. Consequently, it forms a stable solid electrolyte interphase, resulting in dendrite-free electrodeposition of K.