Development of robust electrocatalyst for oxygen reduction reaction (ORR) in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries (SZABs). Herein, constructing a local electric field coupled with chloride ions (Cl^—) fixation strategy in dual single-atom catalysts (DSACs) was proposed, and the resultant catalyst delivered considerable ORR performance in a seawater electrolyte, with a high half-wave potential (E_1/2) of 0.868 V and a good maximum power density (Pmax) of 182 mW·cm⁻² in the assembled SZABs, much higher than those of the Pt/C catalyst (E_1/2: 0.846 V; Pmax: 150 mW·cm⁻²). The in-situ characterization and theoretical calculations revealed that the Fe sites have a higher Cl⁻ adsorption affinity than the Co sites, and preferentially adsorbs Cl⁻ in a seawater electrolyte during the ORR process, and thus constructs a low-concentration Cl⁻ local microenvironment through the common-ion exclusion effect, which prevents Cl⁻ adsorption and corrosion in the Co active centers, achieving impressive catalytic stability. In addition, the directional charge movement between Fe and Co atomic pairs establishes a local electric field, optimizing the adsorption energy of Co sites for oxygen-containing intermediates, and further improving the ORR activity.

The weak adsorption energy of oxygen-containing intermediates on Co center leads to a considerable performance disparity between Co-N-C and costly Pt benchmark in catalyzing oxygen reduction reaction (ORR). In this work, we strategically engineer the active site structure of Co-N-C via B substitution, which is accomplished by the pyrolysis of ammonium borate. During this process, the in-situ generated NH₃ gas plays a critical role in creating surface defects and boron atoms substituting nitrogen atoms in the carbon structure. The well-designed CoB₁N₃ active site endows Co with higher charge density and stronger adsorption energy toward oxygen species, potentially accelerating ORR kinetics. As expected, the resulting Co-B/N-C catalyst exhibited superior ORR performance over Co-N-C counterpart, with 40 mV, and fivefold enhancement in half-wave potential and turnover frequency (TOF). More importantly, the excellent ORR performance could be translated into membrane electrode assembly (MEA) in a fuel cell test, delivering an impressive peak power density of 824 mW·cm^-2, which is currently the best among Co-based catalysts under the same conditions. This work not only demonstrates an effective method for designing advanced catalysts, but also affords a highly promising non-precious metal ORR electrocatalyst for fuel cell applications.

Zinc-iodine (Zn-I₂) batteries have emerged as a compelling candidate for large-scale energy storage, driven by the growing demand for safe, cost-effective, and sustainable alternatives to conventional systems. Benefiting from the inherent advantages of aqueous electrolytes and zinc metal anodes, including high ionic conductivity, low flammability, natural abundance, and high volumetric capacity, Zn-I₂ batteries offer significant potential for grid-level deployment. This review provides a comprehensive overview of recent progress in three critical domains: positive-electrode engineering, zinc anode stabilization, and in situ characterization methods. On the cathode side, anchoring iodine to conductive matrices effectively mitigates polyiodide shuttling and enhances the kinetics of I^-/I₂ conversion. Advanced in situ characterization has enabled real-time monitoring of polyiodide intermediates (I₃^-/I₅^-), offering new insights into electrolyte-electrode interactions and guiding the development of functional additives to suppress shuttle effects. For the zinc anode, innovations such as protective interfacial layers, three-dimensional host frameworks, and targeted electrolyte additives have shown efficacy in suppressing dendrite growth and side reactions, thus improving cycling stability and coulombic efficiency. Despite these advances, challenges remain in achieving long-term reversibility and structural integrity under practical conditions. Future directions include the design of synergistic electrolyte systems, and integrated electrode architectures that simultaneously optimize chemical stability, ion transport and mechanical durability for next-generation Zn-I₂ battery technologies.

The unavailability of high-performance and cost-effective electrocatalysts has impeded the large-scale deployment of alkaline water electrolyzers. Professor Zidong Wei's group has focused on resolving critical challenges in industrial alkaline electrolysis, particularly elucidating hydrogen and oxygen evolution reaction (HER/OER) mechanisms while addressing the persistent activity-stability trade-off. This review summarizes their decade-long progress in developing advanced electrodes, analyzing the origins of sluggish alkaline HER kinetics and OER stability limitations. Professor Wei proposes a unifying “12345 Principle” as an optimization framework. For HER electrocatalysts, they have identified that metal/metal oxide interfaces create synergistic “chimney effect” and “local electric field enhancement effect”, enhancing selective intermediate adsorption, interfacial water enrichment/reorientation, and mass transport under industrial high-polarization conditions. Regarding OER, innovative strategies, including dual-ligand synergistic modulation, lattice oxygen suppression, and self-repairing surface construction, are demonstrated to balance oxygen species adsorption, optimize spin states, and dynamically reinforce metal-oxygen bonds for concurrent activity-stability enhancement. The review concludes by addressing remaining challenges in long-term industrial durability and suggesting future research priorities.