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Assisted by predictions from density functional theory, we used infrared spectroscopy to observe hydride ions introduced into SrTiO3 crystals. 

Abstract The creation of metal‐metal oxide interfaces is an important approach to fine‐tuning catalyst properties through strong interfacial interactions. This article presents the work on developing interfaces between Pt and CeO_xthat improve Pt surface energetics for the hydrogen evolution reaction (HER) within an alkaline electrolyte. The Pt‐CeO_xinterfaces are formed by depositing size‐controlled Pt nanoparticles onto a carbon support already coated with ultrathin CeO_xnanosheets. This interface structure facilitates substantial electron transfer from Pt to CeO_x, resulting in decreased hydrogen binding energies on Pt surfaces, and water dissociation for the HER, as predicted by the density functional theory (DFT) calculations. Electrochemical testing indicates that both Pt specific activity and mass activity are improved by a factor of 2 to 3 following the formation of Pt‐CeO_xinterfaces. This study underscores the significance and potential of harnessing robust interfacial effects to enhance electrocatalytic reactions. 

The phenomenon of plastic flow at ultra-low yield stress in super-low density ductile carbon aerogels from experimental measurements to its theoretical understandingviaatomistic structures and deformation mechanisms. 

Abstract The design of high‐entropy single‐atom catalysts (HESAC) with 5.2 times higher entropy compared to single‐atom catalysts (SAC) is proposed, by using four different metals (FeCoNiRu‐HESAC) for oxygen reduction reaction (ORR). Fe active sites with intermetallic distances of 6.1 Å exhibit a low ORR overpotential of 0.44 V, which originates from weakening the adsorption of OH intermediates. Based on density functional theory (DFT) findings, the FeCoNiRu‐HESAC with a nitrogen‐doped sample were synthesized. The atomic structures are confirmed with X‐ray photoelectron spectroscopy (XPS), X‐ray absorption (XAS), and scanning transmission electron microscopy (STEM). The predicted high catalytic activity is experimentally verified, finding that FeCoNiRu‐HESAC has overpotentials of 0.41 and 0.37 V with Tafel slopes of 101 and 210 mVdec⁻¹at the current density of 1 mA cm⁻²and the kinetic current densities of 8.2 and 5.3 mA cm⁻², respectively, in acidic and alkaline electrolytes. These results are comparable with Pt/C. The FeCoNiRu‐HESAC is used for Zinc–air battery applications with an open circuit potential of 1.39 V and power density of 0.16 W cm⁻². Therefore, a strategy guided by DFT is provided for the rational design of HESAC which can be replaced with high‐cost Pt catalysts toward ORR and beyond.