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Abstract: This study reports the facile synthesis of highly conductive SrRuO3(SRO)–RuO2 composite nanofibre mats and their potential suitability for application in electrochemical capacitors as an active electrode material. SRO–RuO2/poly(vinyl acetate) composite nanofibre mats are electrospun on to a Au-coated SiO2/Si substrate and a Ti substrate, subsequently thermocompressed at 60°C, and calcined at various temperatures (from 350 to 850°C). The calcined SRO–RuO2 nanofibre mats exhibit porous morphologies and bundle shapes composed of multiple-fibrils with a nanoparticle diameter ranging from 20 to 50nm. Single SRO–RuO2 nanofibre and multiple SRO–RuO2 nanofibre mats show high electrical conductivity of 476 and 40.8Scm−1, respectively. Pseudocapacitors using SRO–RuO2 nanofibre mats calcined at 350°C exhibit a high specific capacitance of 192Fg−1 at a scan rate of 10mVs−1. The superior capacitance retention (83.4%) of the SRO–RuO2 nanofibre mats is maintained even at rapid scan rate of 1000mVs−1. [Copyright &y& Elsevier]

Abstract: Polyimide (PI) nanofibers with an average diameter of 300 nm, possessing superior electrolyte wettability and thermal stability, are synthesized by electrospinning a poly(amic acid) (PAA) solution followed by an imidization process. The large pore volume of the PI nanofiber mat can facilitate faster Li+-ion transport and greater rate capability, but it also cause an irreversible increase in cell impedance during long term cycling. To overcome these problems, thin Al2O3 over-layers are coated on both sides of a PI separator via a dip-coating process. The Al2O3-coated PI separators exhibit enhanced capacity, cyclability (95.53% retention after 200 cycles at 1 C), and rate capabilities (78.91% at 10 C) compared to the bare PI separator (68.65% at 10 C) and a commercial polypropylene separator (18.25% at 10 C) with a limited increase of cell impedance. [Copyright &y& Elsevier]