Crystallography modulation of aqueous zinc metal anodes can effectively inhibit their dendrite growth and unfavorable side reactions. However, the ability to directly endow the commercial Zn foils with specific texture is still lacking. In this study, a grain-size-assisted cold-rolling approach is developed to reshape and unify the commercial Zn foils into strong (002) textured Zn. It is revealed that the grain size strongly affects the (002) texture formation during the plastic deformation. By proper annealing treatment, the grain sizes of commercial Zn foils are controlled at ∼30 μm, which favors the formation of strong (002) texture during the following cold-rolling process. The resultant (002) textured Zn foils show better resistance to side reactions and dendrite growth when used as aqueous metal anodes. The strong (002) texture endows the Zn anode with long cycling stability in Zn//Zn symmetric batteries (2800 h at 0.1 mA cm–2, 100 h at 10 mA cm–2) and Zn//porous carbon capacitors (6000 cycles at 2 A g–1). The strategy demonstrated in this work unifies the different textures of commercial Zn foils into strong (002) texture and provides a scalable pathway toward highly reversible Zn anodes for aqueous zinc-ion energy storage devices.

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Atomically dispersed iron immobilized on nitrogen‐doped carbon catalyst has attracted enormous attention for CO2 electroreduction, but still suffers from low current density and poor selectivity. Herein, atomically dispersed FeN5 active sites supported on defective N‐doped carbon successfully formed by a multistep thermal treatment strategy with the aid of dicyandiamide are reported. This dual‐functional strategy can not only construct intrinsic carbon defects by selectively etching pyridinic‐N and pyrrolic‐N, but also introduces an additional N from the neighboring carbon layer coordinating to the commonly observed FeN4, thus creating an FeN5 active site supported on defective porous carbon nanofibers (FeN5/DPCF) with a local 3D configuration. The optimized FeN5/DPCF achieves a high CO Faradaic efficiency (>90%) over a wide potential range of −0.4 to −0.6 V versus RHE with a maximal FECO of 93.1%, a high CO partial current density of 9.4 mA cm−2 at the low overpotential of 490 mV, and a remarkable turnover frequency of 2965 h−1. Density functional theory calculations reveal that the synergistic effect between the FeN5 sites and carbon defects can enhance electronic localization, thus reducing the energy barrier for the CO2 reduction reaction and suppressing the hydrogen evolution reaction, giving rise to the superior activity and selectivity.

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