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This study introduces a new process for the fabrication of an electrode/ceramic multilayer device that uses a mixture of base and noble metals (Cu and Ag) as the inner electrode and is co-fired in air. In order to protect the Cu base metal when exposed to air, the Cu powder was sequentially coated with Ag nanoparticles using a wet process, and borosilicate glass using a sol-gel process. The degrees of oxidation and shrinkage of the glass-coated CuAg during the co-firing process were investigated. The glass-coated CuAg survived without the formation of copper oxide during the binder-burnout process in air at 500 °C. The CuAg was stable and unoxidized even when further heated to 950 °C, which is ascribable to the protection provided by the Ag layer to the Cu exposed to the oxidative atmosphere. The glass-coated CuAg exhibited complicated shrinkage behavior that was similar to that of glass at low temperatures, and to Ag and Cu densification at high temperatures. To examine the electrical performance of the glass-coated CuAg as an inner electrode, a CuAg/(Bi 0.37 Na 0.37 Sr 0.26 )TiO 3 (CuAg/BNST) multilayer-ceramic material was prepared using a conventional tape-casting and stacking procedure. The CuAg-paste binders were evaporated at 500 °C in air, and the CuAg electrode was then sintered at 950 °C in air. The electromechanical performance of the CuAg/BNST ceramic device is similar to that of a AgPd/BNST device, indicating that it can potentially be used as the inner electrode in a multilayer device. [ABSTRACT FROM AUTHOR]

The effects of copper metal organic decomposition (Cu MOD) ink on the electrical and mechanical properties of SWCNT-based flexible transparent electrodes were investigated. In particular, we designed and demonstrated Cu MOD ink as bonding agents between oxidized SWCNT (Ox-SWCNT) and the polyethylene terephthalate (PET) substrate. PET substrates were surface-treated via plasma etching, and ultraviolet/ozone (UV/O 3) treatment was conducted for enhancing the dispersion of SWCNTs. Subsequently, spray coating of numerous times with Ox-SWCNT dispersion and once with Cu MOD ink was applied to the PET substrates at low temperatures. In this way, a robust, flexible, and transparent Ox-SWCNT/Cu@PET composite electrode was fabricated. The as-prepared Ox-SWCNT/Cu@PET composite electrode exhibited good properties, with a sheet resistance of 483.9 Ω/sq and transmittance of 82.1%. Even after 10000 bending cycles and 100 peel-off times, the resistance was only increased by factors of 1.07 and 1.12, respectively, confirming good mechanical robustness. In addition, the electrode exhibited excellent environmental stability; its electrical resistance was only increased by a factor of 1.35 after subjected to harsh environmental conditions (85 °C, 85% relative humidity) for 48 h. These results indicate that the Ox-SWCNT/Cu@PET composite electrodes are promising for wide application as FTCEs. [Display omitted] • Oxidation of SWCNTs and etching of PET enhanced dispersibility and wettability. • Cu NPs from Cu MOD ink improved electrical and mechanical properties of electrodes. • Cu NPs between Ox-SWCNTs and substrate served as bonding agents. • The composite electrodes exhibit good optical, electrical, and mechanical properties. • They can be used in FTCEs with excellent mechanical and environmental stability. [ABSTRACT FROM AUTHOR]

Efficient dye-sensitized solar cells (DSCs) were realized by using multiwalled carbon nanotubes (CNTs) as the counter-electrode catalyst. The catalytic layers were produced from an aqueous paste of mass-produced raw CNTs with carboxymethylcellulose polymer by low-temperature (70 °C) drying. We found that the highly disordered CNTs played the important role of increasing the fill factor of DSCs with electrolytes includinglarge molecules and that the presence of Li the counter charges for I3−/I−redox couples reduced the chemical stability when using the CNT catalyst. Our experiments showed that by replacing the conventional Pt catalyst and Li+based electrolyte with the proposed CNT catalyst and an electrolyte containing 1-butyl-3-methylimidazolium cations instead of Li, the energy conversion efficiency increased from 6.51% to 7.13%. This result suggests that highly defective CNT catalysts prepared by low-temperature drying are viable cost-effective alternatives for DSCs, as long as the electrolytes composition is optimized. [ABSTRACT FROM AUTHOR]