Carbon nanotubes (CNTs) and graphene nanosheets (GNSs) were used as fillers in epoxy composites with the aim of increasing the electrical and thermal conductivities of the composites. The filling of pristine CNTs produced the highest electrical conductivity (r), whereas a high CNT functionalization and the two-dimensional planar structure of GNSs were promising for improving the thermal conductivity. A combination of CNTs and GNSs exploited the advantages of both. When the CNT fraction was larger than 50 wt %, a higher r was obtained. When a small amount of functionalized CNTs was added to the GNSs, the thermal conductivity was also increased. The rheological measurements revealed the lowest complex viscosity for the GNS filling and showed the exciting advantages of an easy processing. As a result, the mixed filling also exhibited a much lower viscosity than the pure CNT fillings.

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Cobalt-free layered perovskite oxides Sm 1-x La x BaFe 2 O 5+δ (x=0-0.5) (SLBFx, for short) have been systematically investigated to evaluate the feasibility as cathode for intermediate temperature SOFC (IT-SOFCs). SLBFx powders with orthorhombic structure synthesized by EDTA-glycine combustion method are compatible with LSGM and SDC electrolytes below 1250 °C. The electrical conductivities of the SLBFx samples significantly increase with the substitution of La for Sm, with the highest conductivity of 37.8 S cm −1 obtained for the SLBF0.5 sample at 600 °C. Among the La-doped SmBaFe 2 O 5+δ series samples, SLBF0.2 has the lowest thermal expansion coefficient (TEC) and the minimum electrode polarization resistance, with a value of 16.51×10 -6 K -1 in 50-800 °C range and 0.24 Ω•cm 2 at 750 °C respectively. The anode supported single cell with SLBF0.2 as cathode can generate a maximum power density of 558 mW cm −2 at 800 °C in humidified H 2 . All things considered, SLBFx materials are good candidates for cobalt-free cathodes in IT-SOFCs.

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