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Aiming to efficiently expedite alkaline overall water splitting (OWS) by addressing challenges such as sluggish kinetics and limited stability, a hollow Fe‐doped Ni(OH)2‐NiS@Ni(OH)2 nanorod array with surface nanosheets is devised, featuring a high‐index Fe‐doped Ni(OH)2(101)‐NiS(211) heterostructural interface and an upshifted d‐band center. This nanoarchitecture intensifies the adsorption and interaction of H2O and OH− reactants on the electrocatalyst surface, suitably bonds the *H intermediate in hydrogen evolution reaction (HER) and accelerates electron movement of *H, minimizes the energy requirement of the rate‐limiting phase (*OH → *O) in oxygen evolution reaction (OER) by facilitating O─H cleavage of *OH and optimally adsorbs *O, amplifies the exposure of surface‐active centers, and ultimately reduces the apparent activation energy. Consequently, the overpotentials are as low as 66.4 mV (HER) and 254.9 mV (OER) at 10 mA cm−2, alongside high turnover frequencies of 142 s−1 (H2) and 279 s−1 (O2) at 100 and 300 mV, respectively, markedly outperforming direct‐electrodeposited analogues. When functioning as a bifunctional electrode in OWS, this material merely requires 1.57 V at 10 mA cm−2 and sustains an operation for 168 h, approaching Pt/C||RuO2 benchmark. [ABSTRACT FROM AUTHOR]

Garnet‐type electrolytes demonstrate promising prospects in the field of solid‐state lithium batteries owing to their superior ionic conductivity and high (electro)chemical stability toward Li metal, whereas the critical issue of Li dendrite growth and even infiltration throughout garnets limits their practical applications. Herein, a hybrid interlayer consisting of Li3Bi alloy embedded in antiperovskite‐type Li3OCl matrix is in situ constructed at Li/Li6.75La3Zr1.75Ta0.25O12 interface by taking the conversion reaction of BiOCl with Li metal. The lithiophilic nature of such interlayer enables an intimate contact of garnet against Li metal, guaranteeing a dramatically reduced interfacial resistance of 27 Ω cm2. In addition, the inside electron‐conducting Li3Bi nanoparticles homogenize the interfacial potential distribution, while the outside ion‐conducting Li3OCl matrix with a bandgap of 5.06 eV blocks electron tunneling from Li bulk. Profiting from such synergistic effect, the resultant Li symmetric cell displays a high critical current density of 1.1 mA cm−2, along with an ultralong cycling life of 1000 h at 0.5 mA cm−2. Furthermore, the corresponding solid LiNi0.6Co0.2Mn0.2O2/Li cell delivers a high cycling stability for 150 times accompanied by a capacity retention of 82%. This study puts forward a potential solution for construction of functional layers at Li/garnet interfaces by making use of in situ conversion reaction. [ABSTRACT FROM AUTHOR]

C/C–SiC composites are promising candidates for heavy‐duty tracked vehicle brake discs. A third‐body layer (TBL) can be formed on the surface of C/C–SiC self‐mated brake discs, which has an important impact on tribological behavior and wear mechanism of brake discs. Herein, the formation conditions and evolution process of TBL and its effect on friction and wear properties were investigated. An appropriate braking pressure and speed (P and V) are beneficial to the cutting of asperities and refinement of wear debris on the contact surface, which are preconditions for the formation of original TBL. The original TBL can be formed under the P·V of 12, 15, and 16, which effectively improve braking stability and reduce the wear rate. During the continuous braking process, the original TBL undergoes growth, stabilization, destruction, and regeneration. Under the frictional heat and compressive stress, wear debris gradually evolves into a uniform and dense TBL. The average coefficient of friction and wear rate reach to the lowest value of.446 and 38.5 × 10−3 cm3/MJ, respectively. A continuous high temperature in the later stages of braking leads to severe oxidative wear. The newly formed TBL covers the original surface to form a multilayered structure, indicating the TBL undergoes destruction and regeneration. [ABSTRACT FROM AUTHOR]