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Abstract Direct ethanol fuel cells have been widely investigated as nontoxic and low-corrosive energy conversion devices with high energy and power densities. It is still challenging to develop high-activity and durable catalysts for a complete ethanol oxidation reaction on the anode and accelerated oxygen reduction reaction on the cathode. The materials’ physics and chemistry at the catalytic interface play a vital role in determining the overall performance of the catalysts. Herein, we propose a Pd/Co@N-C catalyst that can be used as a model system to study the synergism and engineering at the solid-solid interface. Particularly, the transformation of amorphous carbon to highly graphitic carbon promoted by cobalt nanoparticles helps achieve the spatial confinement effect, which prevents structural degradation of the catalysts. The strong catalyst-support and electronic effects at the interface between palladium and Co@N-C endow the electron-deficient state of palladium, which enhances the electron transfer and improved activity/durability. The Pd/Co@N-C delivers a maximum power density of 438 mW cm −2 in direct ethanol fuel cells and can be operated stably for more than 1000 hours. This work presents a strategy for the ingenious catalyst structural design that will promote the development of fuel cells and other sustainable energy-related technologies. 

Employing the strong metal-support interaction (SMSI) effect for promoting the catalyst's activity toward the oxygen reduction reaction (ORR) is promising due to the electronic structure optimization and high utilization efficiency of platinum group metal (PGM) catalysts. Metal oxides as alternative supports for PGMs facilitate intrinsic activity and improve durability as compared to conventional carbon supports. However, the restricted mass and electron transfer at the metal/support interface need to be addressed. Herein, to strengthen the interaction at the metal/support interfaces and improve the utilization efficiency of PGM, an ultralow loading of Pd was embedded in a surface-oxygenated PdNiMnO porous film. The Mn-doping was designed to promote surface oxygenation using a facile anodization process that created sufficiently exposed interfaces between Pd and the support, strengthening the SMSI effects at the Pd/oxygenated support interface for enhancing ORR performance. Furthermore, the Ni-containing oxygenated catalyst served as both the active component for the oxygen evolution reaction (OER) and the functional support for stabilizing Pd, making PdNiMnO a bifunctional catalyst for zinc–air flow batteries (ZAFB). As a proof-of-concept, the ZAFB (PdNiMnO) shows a maximal power density of 211.6 mW cm −2 and outstanding cycling stability for over 2000 h with a minimal voltage gap of 0.69 V at a current density of 10 mA cm −2 , superior to the state-of-the-art catalysts. 

Rechargeable zinc–air batteries (ZABs) show enticing prospects as next‐generation energy conversion and storage technology due to their unique merits of environmental friendliness, low cost, impressive energy density, and high security. However, the dendrite growth, surface passivation, and metal anode corrosion, as well as the sluggish reaction kinetics, deficient bifunctionality, high platinum group metals (PGMs) dependence, and corrosion of carbon‐based materials for air cathodes, are the main problems hindering the large‐scale application of ZABs. Herein, the fundamental principles of ZABs are first introduced. The detailed discussions will be focused on the electrochemical aspects of the metal anode and air cathode by making a comprehensive comparison of the recent progress in the field. Lastly, brief perspectives on the further development of rechargeable ZABs are introduced. This review aims to provide a better understanding of electrode design for ZABs, which will provide guidelines for the design and fabrication of high‐performance and cost‐effective ZABs. 

Abstract To produce efficient ORR catalysts with low Pt content, PtNi porous films (PFs) with sufficiently exposed Pt active sites were designed by an approach combining electrochemical bottom‐up (electrodeposition) and top‐down (anodization) processes. The dynamic oxygen‐bubble template (DOBT) programmably controlled by a square‐wave potential was used to tune the catalyst morphology and expose Pt active facets in PtNi PFs. Surface‐bounded species, such as hydroxyl (OH^*, *=surface site) on the exposed PtNi PFs surfaces were adjusted by the applied anodic voltage, further affecting the dynamic oxygen (O₂) bubbles adsorption on Pt. As a result, PtNi PF with enriched Pt(111) facets (denoted as Pt_3.5 %Ni PF) was obtained, showing prominent ORR activity with an onset potential of 0.92 V (vs. RHE) at an ultra‐low Pt loading (0.015 mg cm⁻²). 

Abstract Electrode stabilization by surface passivation has been explored as the most crucial step to develop long‐cycle lithium‐ion batteries (LIBs). In this work, functionally graded materials consisting of “conversion‐type” iron‐doped nickel oxyfluoride (NiFeOF) cathode covered with a homologous passivation layer (HPL) are rationally designed for long‐cycle LIBs. The compact and fluorine‐rich HPL plays dual roles in suppressing the volume change of NiFeOF porous cathode and minimizing the dissolution of transition metals during LIBs cycling by forming a structure/composition gradient. The structure and composition of HPL reconstructs during lithiation/delithiation, buffering the volume change and trapping the dissolved transition metals. As a result, a high capacity of 175 mAh g⁻¹(equal to an outstanding volumetric capacity of 936 Ah L⁻¹) with a greatly reduced capacity decay rate of 0.012% per cycle for 1000 cycles is achieved, which is superior to the NiFeOF porous film without HPL and commercially available NiF₂‐FeF₃powders. The proposed chemical and structure reconstruction mechanism of HPL opens a new avenue for the novel materials development for long‐cycle LIBs. 

Abstract The Zn‐air battery (ZAB) is attracting increasing attention due to its high safety and preeminent performance. However, the practical application of ZAB relies heavily on developing durable support materials to replace conventional carbon supports which have unrecoverable corrosion issues, severely jeopardizing ZAB performance. Herein, a novel porous FeCo glassy alloy is developed as a bifunctional catalytic support for ZAB. The conducting skeleton of the porous glassy alloy is used to stabilize oxygen reduction cocatalysts, and more importantly, the FeCo serves as the primary phase for oxygen evolution. To demonstrate the concept of catalytic glassy alloy support, ultrasmall Pd nanoparticles are anchored, as oxygen reduction active sites, on the porous FeCo (noted as Pd/FeCo) for ZAB. The Pd/FeCo exhibits a significantly improved electrocatalytic activity for oxygen reduction (a half‐wave potential of 0.85 V) and oxygen evolution (a potential of 1.55 V to reach 10 mA cm⁻²) in the alkaline media. When used in the ZAB, the Pd/FeCo delivers an output power density of 117 mW cm⁻²and outstanding cycling stability for over 200 h (400 cycles), surpassing the conventional carbon‐supported Pt/C+IrO₂catalysts. Such an integrated design that combines highly active components with a porous architecture provides a new strategy to develop novel nanostructured electrocatalysts. 

Abstract The metallic tin (Sn) anode is a promising candidate for next‐generation lithium‐ion batteries (LIBs) due to its high theoretical capacity and electrical conductivity. However, Sn suffers from severe mechanical degradation caused by large volume changes during lithiation/delithiation, which leads to a rapid capacity decay for LIBs application. Herein, a Cu–Sn (e.g., Cu₃Sn) intermetallic coating layer (ICL) is rationally designed to stabilize Sn through a structural reconstruction mechanism. The low activity of the Cu–Sn ICL against lithiation/delithiation enables the gradual separation of the metallic Cu phase from the Cu–Sn ICL, which provides a regulatable and appropriate distribution of Cu to buffer volume change of Sn anode. Concurrently, the homogeneous distribution of the separated Sn together with Cu promotes uniform lithiation/delithiation, mitigating the internal stress. In addition, the residual rigid Cu–Sn intermetallic shows terrific mechanical integrity that resists the plastic deformation during the lithiation/delithiation. As a result, the Sn anode enhanced by the Cu–Sn ICL shows a significant improvement in cycling stability with a dramatically reduced capacity decay rate of 0.03% per cycle for 1000 cycles. The structural reconstruction mechanism in this work shines a light on new materials and structural design that can stabilize high‐performance and high‐volume‐change electrodes for rechargeable batteries and beyond.