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The electric eel is known as the most powerful creature to generate electricity with a discharge voltage up to 860 V and peak current up to 1 A. These surprising properties are the results of billions of years of evolution on the electrical biological structure and bulk, and now have triggered great research interest in electric eel biomimetics for designing innovated configurations and components of energy storage and conversion devices. In this review, first, the bioelectrical behavior of electric eels is surveyed, followed by the physiological structure to reveal the discharge characteristics and principles of electric organs and electrocytes. Additionally, underlying electrochemical mechanisms and models for calculating the potential and current of electrocytes are presented. Central to this review is the recent progress of electric‐eel‐inspired innovations and applications for energy storage and conversion, particularly including novel power sources, triboelectric nanogenerators, and nanochannel ion‐selective membranes for salinity gradient energy harvesting. Finally, insights on the challenges at the moment and the perspectives on the future research prospects are critically compiled. It is suggested that energy‐related electric eel biomimetics will greatly boost the development of next‐generation high performance, green, and functional electronics. [ABSTRACT FROM AUTHOR]

Layered lithium transition‐metal oxides are considered as promising cathodes for new‐generation lithium‐ion batteries due to their high capacity and excellent rate capability. Nevertheless, the approach of preparing precursors is generally restricted to the utilization of wet‐chemical methods. Herein, for the first time, an electrochemical strategy is introduced to prepare Ni1/3Mn1/3Co1/3(OH)2 precursor with the mixing at the atomic level by electrochemically anodized Ni–Mn–Co alloy anode, demonstrating the superiorities of high yield without the process of the extreme alkaline environment and complicated process. Furthermore, the layered LiNi1/3Mn1/3Co1/3O2 cathode is obtained through calcining the mixture of precursors and Li sources under a certain calcined temperature. As anticipated, the initial discharge specific capacities of 183.9 mAh g−1 at 0.1 C with a capacity retention of 79.66% after 120 loops are delivered for LiNi1/3Mn1/3Co1/3O2 cathode with calcining at 930 °C, and it also exhibits superior rate capability with specific capacities of 151.1 and 116.5 mAh g−1 at 1 and 10 C, respectively. Therefore, this innovative approach can be readily extended to prepare other types of lithiated transition metal oxide precursors. [ABSTRACT FROM AUTHOR]

Bimetallic oxides of different metal species and well‐defined nanostructure could lead to a new generation of polymetallic oxide in the energy storage field. Exceptional 1D nanostructured materials are favorable in the electronic transmission of the kinetic processes and confinement effects of electronic structures deriving from the nanoscale dimensions. In this work, an Sb2MoO6 nanorod is successfully prepared for the first time through a facile metathesis reaction process. Then, a thin polyaniline (PANI) layer is coated via the in situ oxidative polymerization of aniline. The Sb2MoO6‐based nanorods are first utilized as anode material for sodium‐ion batteries (SIBs). Benefiting from the synergistic effect of PANI coating and 1D nanostructure, the Sb2MoO6@PANI nanorod electrode presents enhanced sodium storage performances, and a reversible specific capacity of 370.2 mAh g−1 can be retained after 100 cycles. Ex situ electrochemical impedance spectra (EIS) and transmission electron microscopy (TEM) are used to study the evolution process, demonstrating that the PANI coating can alleviate the pulverization of the rod structure and reflect better cycle stability. This work reveals the sodium storage activity of novel Sb2MoO6 nanorods and proposes an efficient strategy to promote its electrochemical properties; it is in great favor of extending the development of anode materials for SIBs. [ABSTRACT FROM AUTHOR]

Black phosphorus, an attractive anode material for sodium‐ion batteries (SIBs), has aroused grand attention because of its high theoretical capacity. Nevertheless, its practical exploration is limited by large volume swelling, followed by rapid capacity decaying. Herein, both large‐area few‐layer phosphorene and low‐defect graphene are obtained by electrochemical exfoliation. The sandwich‐structured phosphorene–graphene hybrid with the simultaneous introduction of PC and POC bonds through chemical activation is employed to heighten the performance of SIBs, leading to a high specific capacity of 2311 mA h g−1 (based on the mass of phosphorene) at 0.1 A g−1 with a capacity retention of 83.9% after 100 loops, which can be ascribed to the flexible space of graphene layers that alleviates the volumetric expansion of phosphorene. Moreover, the stable chemical bonds as the bridge for electrons transferring can immobilize phosphorene and protect phosphorene from cracking during the sodiation/desodiation process. Expectedly, the anode exhibits excellent cycle performance of 200 loops with retained capacities of 1582.6 and 1120.6 mA h g−1 at 1 and 5 A g−1, respectively. Therefore, this electrochemical approach provides a guide for the preparation of other sandwiched 2D materials, which can be applied in high‐performance energy‐storage devices. A sandwich structured phosphorene–graphene hybrid is well‐designed through chemical activation with electrochemically exfoliated phosphorene and graphene. Simultaneously, the formation of PC and POC bonds can protect phosphorene from cracking, and graphene offers an elastic buffer to accommodate the volumetric expansion of phosphorene. This work may provide a guide for the future design of high‐performance anode material for sodium‐ion batteries (SIBs). [ABSTRACT FROM AUTHOR]