出版日期：2009-07-01 00:00:00

著者：Jung, Changhoon; Sánchez-Sánchez, Carlos M.; Lin, Cheng-Lan; Rodríguez-López, Joaquín; Bard, Allen J.

單位：淡江大學化學工程與材料工程學系

出版者：Washington: American Chemical Society

著錄名稱、卷期、頁數：Analytical Chemistry 81(16), pp.7003-7008

摘要：The electrochemical oxidation of formic acid was studied by the tip generation-substrate collection (TG-SC) mode of scanning electrochemical microscopy (SECM), extending the number of applications of SECM in electrocatalysis. Formic acid was generated at a Hg on Au ultramicroelectrode (UME) tip by reduction of CO2 in a 0.1 M KHCO3 solution saturated with this gas. The electrocatalytic activity of different Pd−Co bimetallic compositions was evaluated using a Pd−Co electrocatalyst array formed by spots deposited onto glassy carbon (GC) as a SECM substrate. The SECM tip, which generated a constant formic acid flux, was scanned above the array and the oxidation current generated when formic acid was collected by active electrocatalytic spots was displayed as a function of tip position. This generated a SECM image that showed the electrocatalytic activity of each spot. SECM screening identified Pd50Co50 (Pd/Co = 50:50, atomic ratio) as a better electrocatalyst toward the formic acid oxidation than pure Pd or Pt in 0.1 M KHCO3 solution and this result was confirmed by cyclic voltammetry. Positive feedback was observed for the most active compositions of Pd−Co which suggests fast reaction kinetics and chemical reversibility during the oxidation of formic acid to CO2. Moreover this feedback increases the contrast between active and non-active spots in this imaging mode.

語言：en

ISSN：0003-2700

期刊性質：國外

收錄於：SCI EI

通訊作者：Bard, Allen J.

國別：USA

出版型式：紙本