A bamboo-like nanomaterial composed of V2O5/polyindole (V2O5/PIn) decorated onto the activated carbon cloth was fabricated for supercapacitors. The PIn could effectively enhance the electronic conductivity and prevent the dissolution of vanadium. And the activation of carbon cloth with functional groups is conducive to anchoring the V2O5 and improving surface area, which results in an enhancement of electrochemical performance and leads to a high specific capacitance of 535.5 F/g. Moreover, an asymmetric flexible supercapacitor based on V2O5/PIn@activate carbon cloth and reduced graphene oxide (rGO)@activate carbon cloth exhibits a high energy density (38.7 W h/kg) at a power density of 900 W/kg and good cyclic stability (capacitance retention of 91.1% after 5000 cycles). And the prepared device is shown to power the light-emitting diode bulbs efficiently.

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The zeroth-order multiphysics finite-volume micromechanics has been proposed to model coupled thermo-electro-mechanical behaviors of unidirectional composites embedded with piezoelectric phases. Parametric mapping is implemented within the multiphysics finite-volume theory’s framework, facilitating modeling of multiphase piezoelectric materials with complex microstructures with relatively coarse unit cell discretization. The resulting theory admits piezoelectric materials with complete anisotropy and arbitrary poling direction and enables rapid generation of the entire set of coupled thermo-mechanical, piezoelectric properties, figures of merits, as well as the local fluctuations of fields within the composite microstructures with greater fidelity than its predecessor. The proposed method is verified extensively by comparison with the finite-element homogenization technique, which produces an excellent agreement in a wide range of volume fractions but offers much better stability and efficiency. The contrast with the rectangular theory is also presented and discussed, demonstrating the advantage and the need for the development of parametric formulation. This extension further increases the finite-volume direct averaging micromechanics theory’s range of applicability, providing an attractive standard for investigating multiphase and multiphysics problems with different microstructural architectures and scales against which other approaches may be compared.

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