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Indexed by:期刊论文

Date of Publication:2015-04-01

Journal:NANO-MICRO LETTERS

Included Journals:EI、SCIE、Scopus

Volume:7

Issue:2

Page Number:165-171

ISSN No.:2311-6706

Key Words:Fuel cell; Flow field; Superhydrophobic; Solvent-induced crystallization

Abstract:The CO2-induced capillary blocking in anode flow field is one of the key adverse factors to reduce the performance of a micro-direct methanol fuel cell (mu DMFC). In order to solve this problem, new polycarbonate (PC) flow field plates with nested arrangement of hydrophilic fuel channels and superhydrophobic gas channels were designed, fabricated, and tested in this work. The gas channels were treated with solvent-induced crystallization using acetone solution. The superhydrophobicity with 160A degrees water contact angle and 2A degrees tilting angle was obtained on the PC substrates. A dummy cell using hydrogen peroxide decomposition reaction and a test loop were separately set up to evaluate the flow fields' performance. It was found that a 37 % pressure drop decrease can be obtained in the new serpentine flow field compared with that of the conventional one. The benefit of the new flow field to remove gas bubbles was also confirmed by an in situ visualization study on the dummy cell. Results show that the auxiliary superhydrophobic gas channels can speed up the discharge of the gas bubbles from the flow field, which will in turn improve the mu DMFC performance.