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[Display omitted] The flexible and self-healing supercapacitors (SCs) are considered to be promising smart energy storage devices. Nevertheless, the SCs integrated with flexibility, lightweight, pattern editability, self-healing capabilities and desirable electrochemical properties remain a challenge. Herein, an all-in-one self-healing SC fabricated with the free-standing hybrid film (TCMP) composed of the 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) carried carbon nanotubes (CNTs), manganese dioxide (MnO 2) and polyaniline (PANI) as the electrode, polyvinyl alcohol/sulfuric acid (PVA/H 2 SO 4) gel as the electrolyte and dynamically cross-linked cellulose nanofibers/PVA/sodium tetraborate decahydrate (CNF/PB) hydrogel as the self-healing electrode matrix is developed. The TCMP film electrodes are fabricated through a facile in-situ polymerization of MnO 2 and PANI in TOCNs-dispersed CNTs composite networks, exhibiting lightweight, high electrical conductivity, flexibility, pattern editability and excellent electrochemical properties. Benefited from the hierarchically porous structure and high mechanical properties of TOCNs, excellent electrical conductivity of CNTs and the desirable synergistic effect of pseudocapacitance induced by MnO 2 and PANI, the assembled SC with an interdigital structure demonstrated a high areal capacitance of 1108 mF cm−2 at 2 mA cm−2, large areal energy density of 153.7 μWh cm−2 at 1101.7 μW cm−2. A satisfactory bending cycle performance (capacitance retention up to 95 % after 200 bending deformations) and self-healing characteristics (∼90 % capacitance retention after 10 cut/repair cycles) are demonstrated for the TCMP-based symmetric SC, delivering a feasible strategy for electrochemical energy storage devices with excellent performance, designable patterns and desirable safe lifespan. [ABSTRACT FROM AUTHOR]

Developing high-performance microwave absorption (MA) materials becomes an urgent concern in the field of electromagnetic protection. Constructing porous framework is an efficient approach to MA owing to the abilities of adjusting impedance matching and providing more reflection and scattering paths for electromagnetic waves. Herein, a cellulose nanofibril (CNF)/honeycomb-like carbon-shell encapsulated FeCoNi@C/carbon nanotube (CNT) composite aerogel was fabricated via a facile freeze-drying method. The super-lightweight composites showed a distinctive gradient structure for reflection and scattering inside aerogel pores, micrometer small pores, and nano-fillers on the pore walls. The composite aerogel showed an ideal minimum reflection loss (RL min) of −43.6 dB and remarkable adjustable effective absorption bandwidth (EAB) of 12.18 GHz due to good impedance matching, unique gradient porous structure, and synergies of multiple loss mechanisms. Therefore, this work will provide a viable strategy to improve the MA capability of absorbers by taking full advantage of constructing gradient reflection and scattering porous structure. [Display omitted] [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) heterogeneous flower-like spherical MoS 2 /CNTs composites with worm-like interfaces were successfully fabricated by a simplified solvothermal reaction to achieve superb electromagnetic wave absorption (EWA) properties. The microstructure characteristics, morphology features, EWA performance and associated mechanism of as-prepared specimen were systematically analyzed. The incorporation of MoS 2 resulted in the establishment of a 3D conductive network and a substantial augmentation of the heterogeneous interfaces between MoS 2 and carbon nanotubes (CNTs), thereby inducing an amplified conductance loss and polarization loss, respectively. Moreover, the fabrication of 3D architecture not only enhances the structural robustness of the composites, but also broadens the avenue for electromagnetic wave (EW) reflection and scattering, thus augmenting the absorption of EW energy. As a result of the synergistic effect of augmented attenuation capability as well as optimized impedance matching, the EWA performance of materials was outstanding, with a minimum reflection loss (RL min) of −52.1 dB and an effective absorption bandwidth (EAB) of 1.93 GHz achieved at a thin thickness of 2.46 mm in the X band. This research will serve as a meaningful point of reference for exploring 3D flower-like spherical structure of EW absorber. [Display omitted] • 3D heterogeneous flower-like spherical MoS 2 /CNTs composites were prepared. • MoS 2 /CNTs composites have worm-like interfaces. • Superior EMA performance was achieved with minimum reflection loss was −52.1 dB. • The impedance matching and polarization loss was enhanced with MoS 2. • The electromagnetic wave absorption mechanism was proposed. [ABSTRACT FROM AUTHOR]