Effects of acetone on electrooxidation of 2-propanol in alkaline medium on the Pd/Ni-foam electrode

• Published in: Journal of power sources Vol. 196; no. 6; pp. 3124 - 3128
• Main Authors: Cheng, Yuanhui, Liu, Yao, Cao, Dianxue, Wang, Guiling, Gao, Yinyi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2011; Elsevier
• Subjects: 2-Propanol; Acetone; Anodizing; Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrodes; Electrolytes; Electrooxidation; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Foams; Fuel cells; Nickel; Oxidation; Palladium; Poisoning effect; Surface chemistry; Electrooxidation; Poisoning effect; Palladium; 2-Propanol; Acetone; Electrode poisoning; Alcohol fuel cells; Oxidation; Propanol; Electrochemical reaction
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2010.12.008

▶ Acetone poisons Pd for 2-propanol electrooxidation in alkaline medium. ▶ Acetone poisoning effect is due to its competitive adsorption on Pd with 2-propanol. ▶ Pd on nickel foam electrodes are prepared by a facile chemical replacement method. Acetone is the main product of 2-propanol electrooxidation in both acid and alkaline electrolytes; it always co-exists with 2-propanol in the reaction solution due to its liquid nature. Whether acetone will affect the electrooxidation of 2-propanol has not been well documented, which is a key issue that needs to be addressed for the direct 2-propanol fuel cell. In this study, the influence of acetone on the electrooxidation of 2-propanol in alkaline medium is investigated, using state-of-the-art Pd electrode, by cyclic voltammetry and chronoamperometry. The electrode is prepared using a chemical replacement method, by dipping nickel foam into acidified PdCl2 solution, and characterized by scanning electron microscopy. We found that the presence of acetone adversely affects electrooxidation performance of 2-propanol and substantially reduces the oxidation current of 2-propanol on Pd in alkaline medium. The acetone poisoning effect is interpreted by a competitive adsorption mechanism, in which acetone adsorbs onto Pd surface and occupies the active sites for 2-propanol electrooxidation, leading to a significant decrease in the number of these sites for 2-propanol electrooxidation. The results of this study point out that efficient electrocatalysts for 2-propanol electrooxidation in alkaline electrolytes must be non-adsorptive to acetone besides being highly active to 2-propanol oxidation.