𝔖 Bobbio Scriptorium
✦   LIBER   ✦

The effect of hydrophobicity in alkaline electrodes for passive DMFC

✍ Scribed by Hyea Kim; Junfeng Zhou; Murat Ünlü; Irene Anestis-Richard; Krishna Joseph; Paul A. Kohl

Publisher
Elsevier Science
Year
2011
Tongue
English
Weight
782 KB
Volume
56
Category
Article
ISSN
0013-4686

No coin nor oath required. For personal study only.

✦ Synopsis

The effect of hydrophobicity in alkaline electrodes has been investigated in an effort to improve their performance in passive direct methanol fuel cells. Two approaches have been used to increase the hydrophobicity within the electrodes. One is using a more hydrophobic ionomer, and the other is introducing polytetrafluoroethylene (PTFE) into the catalyst layer. Two types of anion exchange ionomers with different hydrophobicity have been synthesized for this study. The effect of ion exchange capacity, ionic conductivity, and water uptake of the ionomers on the electrode performance has been studied using a half-cell test. The use of a hydrophobic ionomer resulted in enhanced cathode performance even though the ionic conductivity was lower than the more hydrophilic ionomer. Also, the addition of PTFE improved both the cathode and anode performance. The improved alkaline electrode performance was compared to a traditional acid electrode using Nafion as the ionomer. The performance increased threefold as a result of higher hydrophobicity in alkaline electrode.

📜 SIMILAR VOLUMES

On the mechanism of passivation of the c
On the mechanism of passivation of the cadmium electrode in alkaline solutions
✍ A.A. Abdul Azim; K.M. El-Sobki 📂 Article 📅 1972 🏛 Elsevier Science 🌐 English ⚖ 493 KB

The electrochemical behaviour of the Cd electrode in O-1-6 N NaOH has been investigated. Both the potentiostatic and galvanostatic techniques were employed. It has been shown that the electrode surface is primarily covered with a porous layer of Cd(OH), which is precipitated from the solution. Above

Effect of arsenate anion on the dissolut
Effect of arsenate anion on the dissolution and passivation of zinc electrode in slightly alkaline solutions
✍ I. Sánchez de Pinto; C.P. De Pauli; H. Herrera; H. Mishima; B.A. López 📂 Article 📅 1986 🏛 Elsevier Science 🌐 English ⚖ 563 KB

Zinc dissolution and passivation in either arsenate or borate and a mixture of arsenate-borate solutions at pH 8.9 was studied by polarization curves and cyclic voltammetry. The arsenate anion produces an increase on zinc dissolution . Potential sweep rate, rotation speed, temperature, dissolved oxy

The performance of secondary zinc electr
The performance of secondary zinc electrodes in modified alkaline electrolytes I. Galvanostatic passivation studies in alkaline electrolyte
✍ K. Bass; P.J. Mitchell; G.D. Wilcox; J. Smith 📂 Article 📅 1992 🏛 Elsevier Science 🌐 English ⚖ 592 KB

The passivation characteristics of a planar zinc electrode have been examined in 2 M KOH electrolytes containing a variety of additions. The time to passivation has been measured and compared to that of a planar cadmium electrode in 5.3 M KOH. The most promising additives were found to be borate and

Effect of electrolyte concentration on t
Effect of electrolyte concentration on the passivation of Zn in alkaline solutions
✍ A. M. Shams El Din; F. M. Abd El Wahab; S. M. Abd El Haleem 📂 Article 📅 1973 🏛 John Wiley and Sons 🌐 German ⚖ 641 KB

## Abstract In 0,01–0.3 N NaOH solutions and under galvanostatic and potentiostatic conditions Zn(OH)~2~ is formed and is later transformed in oxide of higher valence state. In solutions above 0.3 N ZnO is precipitated after hydrolysis of Zn(OH)~2~ an this ZnO forms a passivating surface layer. Thi