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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