Browsing by Author "Lin, Sheng-Chieh"

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A facile route to prepare PdPt alloys for ethanol electro-oxidation in alkaline electrolyte
(2011-01-31)
Lin, Sheng-Chieh
;
Chen, Jing-Yu
;
Hsieh, Yi-Fan
;
Wu, Pu-Wei
;
材料科學與工程學系
We adopted a displacement reaction in acidic solution that enabled the spontaneous reduction of Pd and Pt cations in conjunction with corrosive dissolution of Ni. The composition for the PdPt was adjusted by varying the concentration of Pd and Pt cations. From SEM images and XRD patterns, the PdPt formed an fcc alloy uniformly deposited on the Ni substrate. Electro-oxidation of ethanol was conducted in alkaline electrolyte for samples of Pd, Pt, and PdPt alloys. In cyclic voltammetric profiles, the Pd(77)Pt(23) revealed the highest electrocatalytic ability in both apparent current and mass activity, followed by Pd(87)Pt(13), Pd, and Pt. Similar behaviors were observed in life time measurements in which stable performances for ethanol electro-oxidation were obtained. (C) 2010 Elsevier B.V. All rights reserved.
Conformal deposition of Ni-P on anodic aluminum oxide template
(2008)
Lin, Sheng-Chieh
;
Lai, Chun-Han
;
Wu, Pu-Wei
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A nanoporous semiconducting template was fabricated by conformal deposition of Ni-P over anodic aluminum oxide (AAO). Electroless plating was conducted in repeated steps of sensitization, activation, and deposition using NaH2PO2 as a reducing agent. Variables including pH, temperature, time, and additive were studied for conformal deposition within the pore channels without clogging the openings prematurely. We demonstrated concentric Ni-P tubes with an inner diameter of 84 nm at 10 mu m length. Resistivity of the AAO template was determined at 39.6 Omega cm for through-channel direction. Incorporation of the semiconducting AAO structure with established template synthesis technologies opens up the opportunity for numerous devices. (C) 2007 The Electrochemical Society.
Templated fabrication of nanostructured Ni brush for hydrogen evolution reaction
(2010-10-01)
Lin, Sheng-Chieh
;
Chiu, Yu-Fan
;
Wu, Pu-Wei
;
Hsieh, Yi-Fan
;
Wu, Cheng-Yeou
We fabricated a nanostructured brush by carrying out Ni deposition on a through-channel anodic aluminum oxide (AAO) template, followed by removal of the AAO skeleton. The AAO was prepared by a two-step anodization process resulting in pore diameter and thickness of 350 nm and 40 mu m, respectively. Subsequently, the AAO underwent an electroless deposition involving sensitization, activation, and Ni plating, in conjunction with polyethylene glycol used as the inhibitor to prevent premature closing of pore opening. After deliberate control in relevant parameters, we obtained a conformal Ni overcoat along every pore channel leading to a reduced average pore diameter of 78 nm. Afterward, the sample was immersed in a KOH solution to remove the AAO structure, forming freestanding Ni tubules in a brush configuration. The nanostructured brush revealed considerable enhancement for hydrogen evolution reaction in both current-potential polarization and galvanostatic measurements, which were attributed to the increment in apparent surface area.
Templated fabrication of nanostructured Ni brush for hydrogen evolution reaction
(2010-10-01)
Lin, Sheng-Chieh
;
Chiu, Yu-Fan
;
Wu, Pu-Wei
;
Hsieh, Yi-Fan
;
Wu, Cheng-Yeou
We fabricated a nanostructured brush by carrying out Ni deposition on a through-channel anodic aluminum oxide (AAO) template, followed by removal of the AAO skeleton. The AAO was prepared by a two-step anodization process resulting in pore diameter and thickness of 350 nm and 40 mu m, respectively. Subsequently, the AAO underwent an electroless deposition involving sensitization, activation, and Ni plating, in conjunction with polyethylene glycol used as the inhibitor to prevent premature closing of pore opening. After deliberate control in relevant parameters, we obtained a conformal Ni overcoat along every pore channel leading to a reduced average pore diameter of 78 nm. Afterward, the sample was immersed in a KOH solution to remove the AAO structure, forming freestanding Ni tubules in a brush configuration. The nanostructured brush revealed considerable enhancement for hydrogen evolution reaction in both current-potential polarization and galvanostatic measurements, which were attributed to the increment in apparent surface area.