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High fabrication cost, chemical instability, and complex immobilization of enzyme molecules are critical issues of enzyme‐based glucose sensors. Designing state‐of‐the‐art, binder‐free, and non‐enzymatic glucose sensing probes plays an imperative role to cope with the aforementioned issues. 3D carbonaceous nanomaterials coated with transition metal vanadates (TMVs) are a favorable biomimetic platform for glucose quantification. Peculiar hierarchical structure, enhanced conductivity, synergistic interaction, multiple oxidation states, and high catalytic activity would make such composite a potential contender for non‐enzymatic glucose sensing. Herein, 3D helical‐shaped carbon nanocoils (CNCs) are grown on nickel foam (NF) via chemical vapor deposition method to prepare a robust CNCs/NF scaffold. Then, a hydrothermal route is followed to grow interconnected free‐standing Ni3V2O8 nanosheets (NSs) on CNCs/NF scaffold. This novel and binder‐free Ni3V2O8 NSs/CNCs/NF hierarchical composite possesses superior electrochemical active area (ECSA) and exceptional electrochemical efficacy. Amperometric analysis exhibits extremely prompt detection time (0.1 s), elevated sensitivity (5214 µA mM−1 cm−2), and low detection limit (0.04 µM). Developed sensor demonstrates appreciable recoveries (93.3 to 103.3%) regarding glucose concentration in human serum. The appealing analytical results show that deployment of a 3D helical‐shaped hierarchical smart scaffold can be an effective strategy for developing efficient and advanced non‐enzymatic glucose sensors. [ABSTRACT FROM AUTHOR]

Advanced flexible supercapacitors with high energy/power density are an imperative research objective. In this study, a dually activated carbon cloth is designed as the functional current collector for supercapacitors. An electrodeposition technique is used for engineering Manganese Dioxide (MnO 2) nanoflakes and profiting from a Poly (3,4 ethylene dioxythiophene; PEDOT) shield layer, a Li+-based neutral electrolyte high-performance freestanding asymmetric supercapacitors is constructed. The activated carbon cloth (ACC) provides an efficient electron-carrying route and the hierarchical nanostructure of the ACC@MnO 2 @PEDOT electrode. The integrated ACC@MnO 2 @PEDOT electrode exhibited exceptional capacitance performance of 1882.5 mF cm−2 (current density 1 mA cm−2) in 1.5 M aqueous LiCl electrolyte benefiting from ACC scaffold, the pseudocapacitive activity of MnO 2 and substantial conductivity of the PEDOT polymer. Fabricating the structured electrode into an asymmetric supercapacitor revealed an enhanced areal energy density and an areal power density. The fabricated device demonstrated a broad voltage window of 1.8 V and extraordinary cycling stability of 94.6% after 10000 charge-discharge cycles. The unique scaffold, conducting PEDOT polymer, and MnO 2 nanoflakes synergistically improved the cyclic performance and rate proficiency of the electrode, resulting in a supercapacitor with bendable electrical energy storage applications. [Display omitted] • Introduction of a unique activation for carbon cloth deployed as a scaffold. • Electrodeposition of MnO 2 nanoflakes and PEDOT shield layer for SC electrode. • The integrated electrode showed excellent specific capacitance of 1882.5 mF cm−2. • The ASC with high areal energy density/power density (0.25 mW h cm−2/1.259 mW cm−2). • A broad voltage window of 1.8 V with cycling life of 94.6% after 10000 GCD cycles. [ABSTRACT FROM AUTHOR]

The fabrication of low-cost, effective, and highly integrated nanostructured materials through simple and reproducible methods for high-energy-density supercapacitors is highly desirable. Herein, an activated carbon cloth (ACC) is designed as the functional scaffold for supercapacitors and treated hydrothermally to deposit NiCo nanoneedles working as internal core, followed by a dip-dry coating of NiOOH nanoflakes core-shell and uniform hydrothermal deposition of CoMoO 4 nanosheets serving as an external shell. The structured core-shell heterostructure ACC@NiCo@NiOOH@CoMoO 4 electrode resulted in exceptional specific areal capacitance of 2920 mF cm -2 and exceptional cycling stability for 10 000 cycles. Moreover, the fabricated electrode is developed into an asymmetric supercapacitor which demonstrates excellent areal capacitance, energy density, and power density within the broad potential window of 1.7 V with a cycling life of 92.4% after 10 000 charge-discharge cycles, which reflects excellent cycle life. The distinctive core-shell structure, highly conductive substrate, and synergetic effect of coated material results in more electrochemical active sites and flanges for effective electrons and ion transportation. This unique technique provides a new perspective for cost-efficient supercapacitor applications., (© 2023 Wiley-VCH GmbH.)

Well-organized substrate materials are of considerable significance in the development of energy-efficient pseudocapacitor electrodes. Herein, functionalized three-dimensional (3D) carbon nanocoils on nickel foam (CNCs/NF) have been used as the substrate to grow faradaic nickel cobaltite (NiCo2O4) via a solvothermal method. The arrays of NiCo2O4 were assembled by interconnected ultrathin nanosheets with random inter-particle pores. The number of electroactive sites increased specifically because of the porous feature of NiCo2O4 nanosheets and the 3D structure of CNCs/NF. Moreover, the CNCs/NF network aided the electrolyte ions in diffusing deeply within the architecture. The NiCo2O4/CNCs/NF composite exhibited an outstanding specific capacitance of 2821 F g-1 at the current density of 1 A g-1, a remarkable rate capability (82.4%) and long cyclic stability (91.7% after 3000 cycles). Such encouraging electrochemical performance was attributed mainly to the synergistic interactions of NiCo2O4 arrays and CNCs/NF substrate that helped achieve efficient redox reactions, enhanced ion diffusivity and excellent electron conductivity. In summary, this binder-free NiCo2O4/CNCs/NF composite electrode paves a way towards the synthesis of highly efficacious electrodes for supercapacitors.