Abstract Anode‐free all‐solid‐state batteries (AF‐ASSBs) have received significant attention as a next‐generation battery system due to their high energy density and safety. However, this system still faces challenges, such as poor Coulombic efficiency and short‐circuiting caused by Li dendrite growth. In this study, the AF‐ASSBs are demonstrated with reliable and robust electrochemical properties by employing Cu–Sn nanotube (NT) thin layer (~1 µm) on the Cu current collector for regulating Li electrodeposition. Li x Sn phases with high Li‐ion diffusivity in the lithiated Cu–Sn NT layer enable facile Li diffusion along with its one‐dimensional hollow geometry. The unique structure, in which Li electrodeposition takes place between the Cu–Sn NT layer and the current collector by the Coble creep mechanism, improves cell durability by preventing solid electrolyte (SE) decomposition and Li dendrite growth. Furthermore, the large surface area of the Cu–Sn NT layer ensures close contact with the SE layer, leading to a reduced lithiation overpotential compared to that of a flat Cu–Sn layer. The Cu–Sn NT layer also maintains its structural integrity owing to its high mechanical properties and porous nature, which could further alleviate the mechanical stress. The LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM)|SE|Cu–Sn NT@Cu cell with a practical capacity of 2.9 mAh cm −2 exhibits 83.8% cycle retention after 150 cycles and an average Coulombic efficiency of 99.85% at room temperature. It also demonstrates a critical current density 4.5 times higher compared to the NCM|SE|Cu cell.

Proton-exchange-membrane water electrolysis (PEMWE) requires an efficient and durable bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, Ir-based electrocatalyst is designed using the high entropy alloy (HEA) platform of ZnNiCoIrX with two elements (X: Fe and Mn). A facile dealloying in the vacuum system enables the construction of a nanoporous structure with high crystallinity using Zn as a sacrificial element. Especially, Mn incorporation into HEAs tailors the electronic structure of the Ir site, resulting in the d-band center being far away from the Fermi level. Downshifting of the d-band center weakens the adsorption energy with reaction intermediates, which is beneficial for catalytic reactions. Despite low Ir content, ZnNiCoIrMn delivers only 50 mV overpotential for HER at -50 mA cm^-2 and 237 mV overpotential for the OER at 10 mA cm^-2 . Furthermore, ZnNiCoIrMn shows almost constant voltage for the HER and OER for 100 h and a high stability number of 3.4 × 10⁵ n_hydrogen n_Ir ^-1 and 2.4 × 10⁵ n_oxygen n_Ir ^-1 , demonstrating the exceptional durability of the HEA platform. The compositional engineering of ZnNiCoIrMn limits the diffusion of elements by high entropy effects and simultaneously tailors the electronic structure of active Ir sites, resulting in the modified cohesive and adsorption energies, all of which can suppress the dissolution of elements.

Abstract Anode‐free all‐solid‐state batteries (AF‐ASSBs) have received significant attention as a next‐generation battery system due to their high energy density and safety. However, this system still faces challenges, such as poor Coulombic efficiency and short‐circuiting caused by Li dendrite growth. In this study, the AF‐ASSBs are demonstrated with reliable and robust electrochemical properties by employing Cu–Sn nanotube (NT) thin layer (~1 µm) on the Cu current collector for regulating Li electrodeposition. Li x Sn phases with high Li‐ion diffusivity in the lithiated Cu–Sn NT layer enable facile Li diffusion along with its one‐dimensional hollow geometry. The unique structure, in which Li electrodeposition takes place between the Cu–Sn NT layer and the current collector by the Coble creep mechanism, improves cell durability by preventing solid electrolyte (SE) decomposition and Li dendrite growth. Furthermore, the large surface area of the Cu–Sn NT layer ensures close contact with the SE layer, leading to a reduced lithiation overpotential compared to that of a flat Cu–Sn layer. The Cu–Sn NT layer also maintains its structural integrity owing to its high mechanical properties and porous nature, which could further alleviate the mechanical stress. The LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM)|SE|Cu–Sn NT@Cu cell with a practical capacity of 2.9 mAh cm −2 exhibits 83.8% cycle retention after 150 cycles and an average Coulombic efficiency of 99.85% at room temperature. It also demonstrates a critical current density 4.5 times higher compared to the NCM|SE|Cu cell.

Proton-exchange-membrane water electrolysis (PEMWE) requires an efficient and durable bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, Ir-based electrocatalyst is designed using the high entropy alloy (HEA) platform of ZnNiCoIrX with two elements (X: Fe and Mn). A facile dealloying in the vacuum system enables the construction of a nanoporous structure with high crystallinity using Zn as a sacrificial element. Especially, Mn incorporation into HEAs tailors the electronic structure of the Ir site, resulting in the d-band center being far away from the Fermi level. Downshifting of the d-band center weakens the adsorption energy with reaction intermediates, which is beneficial for catalytic reactions. Despite low Ir content, ZnNiCoIrMn delivers only 50 mV overpotential for HER at -50 mA cm^-2 and 237 mV overpotential for the OER at 10 mA cm^-2 . Furthermore, ZnNiCoIrMn shows almost constant voltage for the HER and OER for 100 h and a high stability number of 3.4 × 10⁵ n_hydrogen n_Ir ^-1 and 2.4 × 10⁵ n_oxygen n_Ir ^-1 , demonstrating the exceptional durability of the HEA platform. The compositional engineering of ZnNiCoIrMn limits the diffusion of elements by high entropy effects and simultaneously tailors the electronic structure of active Ir sites, resulting in the modified cohesive and adsorption energies, all of which can suppress the dissolution of elements.

We report an intercalation-type Cu 1.8 S cathode material with porous spherical microparticles for all-solid-state batteries (ASSBs), which achevies superior cycling stability and high energy density by suppressing interfacial side reactions.

Science requires reproducibility. However, the replication crisis in medical, psychological, biological, and social sciences has revealed that satisfactory reproducibility is only achieved when it is measured, investigated, and critically discussed. Despite the inherent sensitivity and complexity of heterogeneous electrocatalysis, little is known about the reproducibility of its experimental protocols. Herein, we present a global interlaboratory study of nickel-iron-based oxygen evolution electrocatalysts, revealing substantial reproducibility challenges. Using a process characterization tool of the pharmaceutical industry, we identify that these reproducibility challenges originate from undescribed but critical process parameters. Finally, we discuss solution approaches to address electrocatalysis’ inherent experimental complexity without affecting academia’s explorative nature. This report sets a data-based foundation for a critical discussion of reproducibility and a following credibility revolution in heterogeneous catalysis research.

The Lewis acidity of Ni 2+ and Fe 3+ ions in a layered double hydroxide (LDH) was enhanced by incorporating the lanthanide dopant Ce, tuning the surface electronic configurations to prefer OH* adsorption over Cl* adsorption.

Hydrogen evolution reaction (HER) under alkaline conditions is determined by the water dissociation process. Strengthening the adsorption ability of the electrocatalyst is crucial to promoting water dissociation in the alkaline HER, whereas too-intense adsorption will poison the active sites. Herein, the adsorption ability of NiFeP is modulated by nonmetal F doping for an efficient and durable alkaline HER. F incorporation in NiFeP (NiFePF) tailors the electronic structure of Ni, Fe, and P, optimizing the adsorption of ^*OH/^*H on the active sites. The balanced ^*OH/^*H adsorption facilitates the water dissociation and hydrogen evolution of NiFePF, exhibiting the smaller overpotential of 233 mV at 100 mA cm^-2. Furthermore, NiFePF achieves 1 A cm^-2 at an overpotential of only 231 mV under 30 wt% KOH. The balanced ^*OH/^*H adsorption ability in NiFePF facilitates the desorption of ^*OH and alleviates the poisoning active center, limiting the surface hydroxylation of NiFePF to a few nanometers. This enables NiFePF to remain stable for 360 h, demonstrating its commercial potential.