Ba(Zr 0.2 Ti 0.8 )O 3 (BZT) and 2 mol% Mn additional doped BZT (Mn-BZT) thin films were deposited on Pt/Ti/SiO 2 /Si by the pulsed laser deposition (PLD) technique under the same growth conditions. X-ray diffraction scans showed that both films were polycrystalline and preferentially (1 1 1)-oriented, and an enhanced crystallization effect was obtained after Mn doping. The parallel-plate capacitors of Au/BZT/Pt and Au/Mn-BZT/Pt were prepared to investigate the electric properties, respectively. The remanent polarization and the coercive electric field for Mn-doped BZT film were both smaller than those of undoped BZT film. Furthermore, Mn-doped BZT film exhibited a higher dielectric constant of 460 at zero bias, larger dielectric tunability of 69.0% and lower dielectric loss of 5.0‰ under an applied electric field of 615 kV cm −1 than those of undoped BZT film. The figure of merit for preferentially (1 1 1)-oriented BZT thin film was greatly enhanced from 94 to 138 by Mn doping. The enhanced dielectric behaviour by Mn doping could be mainly attributed to the decrease in electron concentration and oxygen vacancies and the reorientation of the defect complex.

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When carbon nanocoils (CNCs) are used in fuel cell electrodes, the diffusion of fuel and gas, and the removal of reaction products, becomes considerably smoother. In this paper, we used CNC as an anode or cathode catalyst support material in direct methanol fuel cells (DMFCs). Other carbon nanoparticles, Arc-Black (AcB) and Vulcan, were also used as catalyst supports to compare with the CNCs. Catalysts were loaded onto nanocarbon materials using the polyol method. We measured the methanol oxidation current of PtRu catalysts loaded on the carbon nanomaterials and the catalyst on CNC showed the highest current. Compared with the catalyst layers of AcB and Vulcan, the catalyst layer of CNCs was confirmed to have several voids. As for the cathode catalysts, the power density of Pt/CNC was 1.2 times higher than that of Pt/Vulcan and 1.6 times higher than that of Pt/AcB.

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