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The inhomogeneous plating/stripping of Zn anode, attributed to dendrite growth and parasitic reactions at the electrode/electrolyte interface, severely restricts its cycling life‐span. Here, trace zwitterions (trifluoroacetate pyridine, TFAPD) are introduced into the aqueous electrolyte to construct a multifunctional interface that enhances the reversibility of Zn anode. The TFA− anions with strong specific adsorption adhere onto the Zn surface to reconstruct the inner Helmholtz plane (IHP), preventing the hydrogen evolution and corrosion side reactions caused by free H2O. The Py+ cations accumulate on the outer Helmholtz plane (OHP) of Zn anode with the force of electric field during Zn2+ plating, forming a shielding layer to uniformize the deposition of Zn2+. Besides, the adsorbed TFA− and Py+ promote the desolvation process of Zn2+ resulting in fast reaction kinetics. Thus, the Zn||Zn cells present an outstanding cycling performance of more than 10000 hours. And even at 85 % utilization rate of Zn, it can stably cycle for over 200 hours at 10 mA cm−2 and 10 mAh cm−2. The Zn||I2 full cell exhibits a capacity retention of over 95 % even after 30000 cycles. Remarkably, the Zn||I2 pouch cells (95 mAh) deliver a high‐capacity retention of 99 % after 750 cycles. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER), as a pivotal half-reaction, significantly hinders the advancement of energy conversion efficiency. Metal electrodeposition on catalysts has been demonstrated to effectively enhance the HER reactivity. Here, Ni3S2–Fe–Ni with a multilayer structure was obtained by the electrodeposition of Ni3S2 with dopants Fe/Ni, in which a number of active sites were achieved and the intrinsic conductivity of the catalyst was well improved. Elemental analyses revealed the multilayer structure consisting of Ni3S2, NiS, and Fe. The Ni3S2–Fe–Ni catalyst exhibited impressive electrochemical performance due to optimization of its structure with the overpotentials of the HER and OER of only 83 and 190 mV. Notably, at a higher current density of 100 mA cm−2, the overpotentials for the HER and OER are only 339 and 365 mV. As a bifunctional electrocatalyst, its total splitting voltage was only 1.55 V. The catalysis performance remained nearly unchanged even after 48 h of stability testing. Finally, density functional theory (DFT) calculations revealed that the potential barriers in each reaction step of the OER are evenly distributed, and optimizing the Ni3S2 structure with iron and nickel atoms reduced the reaction energy barriers during the electrochemical process, improving the OER/HER performance. [ABSTRACT FROM AUTHOR]

The bolted joint is widely used to connect different composite structures in the aerospace field, and the joint is usually the weakest part, and its performance is widely influenced by temperature. This paper aims to investigate the static tensile behavior of the composite‐aluminum four‐nailed joint structure at different temperatures. Carbon fiber epoxy resin matrix composites with a layup of [(0/45)2s]2 are selected to fabricate specimens, and the test temperatures are room temperature (RT, 25 °C), 60 °C, 100 °C, and 150 °C, respectively. The surface strain field and damage evolution inside the specimens are monitored at different stages of the loading process by combining the digital image correlation (DIC) and X‐ray computed tomography (CT) techniques. During the loading process at RT, a sudden drop in load occurs after structural yielding, and the following secondary bearing is observed; however, at higher temperatures, the load continuously decreases until final failure after it reaches the peak value. Moreover, the rearrangement of stress distribution around the bolts at higher temperatures relieves the asymmetric secondary bending of the joint. The experimental findings in this study provide valuable guidance for the structural design and safety assessment for composite‐aluminum bolted joints at different temperatures. Highlights: The loading process shows five stages at RT and four stages at higher temperatures.Extrusion damage led by shear cracks appears earlier at higher temperatures.Load on the upper and lower bolts is closer as the temperature increases.Higher temperatures relieve the asymmetric secondary bending of the joint. [ABSTRACT FROM AUTHOR]