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The chemical stability of potassium substituted for A-site of SrCe 0.95 Y 0.05 O 3 specimens was examined under CO 2 atmosphere treated at 600 °C and further analyzed by X-ray diffractometer to see their CO 2 -resisted capabilities. According to thermodynamic data, the Gibbs free energy of CeO 2 was lower than that of SrCO 3 at the temperature of 600 °C. Thus the formation of CeO 2 might be faster than that of SrCO 3 in SrCeO 3− based materials under CO 2 atmosphere. Unfortunately, the chemical stability of SrCe 0.95 Y 0.05 O 3 materials in CO 2 atmosphere was reduced with increasing potassium-substituted amount. The microstructures of Sr 1− x K x Ce 0.95 Y 0.05 O 3 sintered specimens were identified using field emission scanning electron microscope. The conductivity in moisture H 2 atmosphere (RH 30%) was increased with increasing potassium-substituted concentration. The conductivity reached a maximum of 0.0081 Scm -1 at 900 °C for Sr 0.95 K 0.05 Ce 0.95 Y 0.05 O 3 sintered specimens in moisture H 2 atmosphere (RH 30%). Potassium substituted for A-site of SrCe 0.95 Y 0.05 O 3 could improve the conductivity but not CO 2 -resisted capability.

A Fe–Cr alloy, used for metallic interconnects, was coated with a protective layer of lanthanum strontium manganite (LSMO) using the aerosol deposition method (AD). The effects of the LSMO protective layer, which was coated on the Fe–Cr interconnects using AD, on the area specific resistance (ASR) during high temperature oxidation and the Cr evaporation behaviors were systematically investigated in this paper. The microstructures, morphologies, and compositions of the oxidized scales that appeared on the LSMO-coated Fe–Cr alloy after annealing at 800 °C for 750 h in air were examined using SEM equipped with EDS. The EPMA mapping of the LSMO-coated Fe–Cr interconnects undergoing long term, high-temperature oxidation was used to explain the formation layers of the oxidized scale, which consists of (Mn,Cr) 3 O 4 and Cr 2 O 3 layers. Moreover, the experimental results revealed that the AD process is a potential method for preparing denser protective layers with highly desirable electrical properties for metallic interconnects.

Five selected alloys, Crofer22 APU, Crofer H, ss441 and two different ZMG232 were selected for a cautious study. Our major focus is on the materials' resistance to oxidation and Cr evaporation. Both issues remain to be major concerns in many applications, particularly for interconnects in solid oxide fuel cells. For the part of oxidation, samples of five alloys are placed in an oven heating at 800 °C for 250 h. The microstructures, morphologies and compositions of samples after oxidation are analyzed by SEM, XRD, EDS on surfaces and cross-sections. Electrical resistance of samples during oxidation is measured by four-point probe to obtain their variations over time. An assembly, of which two alumina plates sandwiching the samples alloys, is specifically designed to test the resistance of specimens to Cr evaporation, which is gauged by the amount of deposited Cr on the two alumina plates under long-hour oxidation. Experimental results revealed that Crofer22 APU has a better performance than others after long-hour oxidation with thinner oxidized layer, lower electrical resistance and less Cr evaporation.

An amperometric sensor for monitoring ethanol concentration using a Ni–Pt alloy electrode has been developed. The films of Ni–Pt alloy were electrodeposited under various potentials on an Au/Al2O3 substrate. To examine the effects of Ni–Pt alloy films on the sensing performance, the electrodes with various Ni:Pt atomic proportions of 100:0, 25:75, 70:30, 82:18 and 0:100 were prepared and tested. X-ray diffraction and scanning electron microscope analyses indicate that Ni atoms of Ni–Pt alloy electrodes are inserted in the Pt lattice and a pyramid-like structure is formed with an increase of Pt content in the film. All the prepared electrodes have a linear relationship between response current and ethanol concentration for the detection range of 50 to 300 ppm ethanol in alkaline solutions. With an increase of Pt content in the film, the response time of the Ni–Pt alloy electrodes was reduced whereas the sensitivity was decreased. The sensor with 70 at.% Pt in the film was most stable with the duration over a 63-day-period. The sensitivity of the Ni–Pt alloy electrodes for detecting glucose, various alcohols and acids have also been studied.

Thin films of RuO2 were prepared by reactive rf sputtering from a Ru target in an Ar+O2 atmosphere, with the oxygen concentration varying from 10% to 100%. The resistivity, deposition rate, crystal structure, surface morphology, composition and chemical binding state of RuO2 films were investigated. RuO2 films sputtered with 33% or more oxygen exhibited lower deposition rate and lower resistivity relative to the films sputtered with 10 or 20% oxygen. The O/Ru ratios of the RuO2 films sputtered with 10, 20 and 50% oxygen were similar; however, evident rutile structure was only observed for films sputtered with 50% O2. The low resistivity is related with the crystallinity of the films. The RuO2 films sputtered with 50% oxygen were annealed in flowing oxygen at 200–750°C for 30 min. The film resistivity was further decreased with increasing annealing temperature and reached a minimum value of 110 μΩ cm after annealing at 650°C. From X-ray diffraction and scanning electron microscopy analyses, the decrease of film resistivity upon annealing is attributed to the grain growth and reduction of lattice spacing in the RuO2 films.

Corrigendum to “Determination of alcohols using a Ni–Pt alloy amperometric sensor” [Thin Solid Films 516 (2008) 5210–5216] Jian-Jia Huang , Weng-Sing Hwang ⁎, Yu-Ching Weng , Tse-Chuan Chou b,c a Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan b Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan c Department of Chemical Engineering, Tatung University, Taipei, Taiwan