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Exploring an efficient nonnoble metal catalyst for hydrogen evolution reaction (HER) is critical for industrial alkaline water electrolysis. However, it remains a great challenge due to the additional energy required for H─OH bond cleavage and the lack of enough H2O adsorption sites for most catalysts. Herein, the integration of oxophilic Eu2O3 with NiCo alloy with evoked multisite synergism to facilitate water dissociation for alkaline HER is proposed. The optimized Eu2O3‐NiCo exhibits excellent HER activity with a low overpotential of only 60 mV at 10 mA cm−2 and good electrochemical stability, which is superior to that of Eu2O3‐free NiCo and comparable to benchmark Pt/C. The key roles of Eu2O3 on the enhanced HER performance of Eu2O3‐NiCo are identified by in situ Raman spectroscopy and theoretical calculations. It is discovered that the Eu2O3 with strong oxophilicity facilitates the adsorption of H2O and the breakage of H─OH bonding while evoking the electron redistribution at Eu2O3/NiCo interface and accelerating the Volmer step in alkaline HER. Furthermore, the obtained Eu2O3‐NiCo as both anode and cathode displays excellent overall water‐splitting activity and stability in 1.0 M KOH solution. It is believed that this study provides an important inspiration to design high‐performance electrocatalysts toward HER based on rare‐earth materials. [ABSTRACT FROM AUTHOR]

Bamboo has a functionally-graded microstructure that endows it with a combination of desirable properties, such as high failure strain, high toughness, and a low density. As a result, bamboo has been widely used in load-bearing structures. In this work, we study the use of bamboo-inspired void patterns to geometrically improve the failure properties of structures made from brittle polymers. We perform finite element analysis and experiments on 3D-printed structures to quantify the effect of the shape and spatial distribution of voids on the fracture behavior. The introduction of periodic, uniformly distributed voids in notched bend specimens leads to a 15-fold increase in the fracture energy relative to solid specimens. Adding a gradient to the pattern of voids leads to a cumulative 55-fold improvement in the fracture energy. Mechanistically, the individual voids result in crack blunting, which suppresses crack initiation, while neighboring voids redistribute stresses throughout the sample to enable large deformation before failure., (Creative Commons Attribution license.)