Hydrophilic/hydrophobic membrane electrode of ionic liquids

Abstract

The invention belongs to the technical field of membrane electrode preparation, and particularly relates to a hydrophilic / hydrophobic membrane electrode of ionic liquids. An anode catalyst layer is prepared from the hydrophilic proton type ionic liquid and a catalyst, and a cathode catalyst layer is prepared from a hydrophobic and oxytropic proton type ionic liquid and a catalyst. A self-humidifying membrane electrode is prepared by taking the ionic liquids with special physical and chemical properties as raw materials for preparing the catalyst layers, so that the problem that the charge transfer resistance is increased due to the fact that inorganic oxide is taken as an additive for preparing the self-humidifying membrane electrode is effectively solved; the selected ionic liquids have negligible volatility, so the ion transmission capacity and stability of the membrane electrode are greatly improved; and meanwhile, the hydrophobic ionic liquid can be adsorbed into the pore channelsof the catalyst under a high-vacuum condition through a continuous vacuumizing treatment process, so that the ionic liquid can be uniformly dispersed on each surface of the catalyst.

Description

technical field [0001] The invention belongs to the technical field of membrane electrode preparation, and in particular relates to a hydrophilic / hydrophobic membrane electrode related to ionic liquid. Background technique [0002] Membrane electrode, as a key component in the hydrogen-oxygen fuel cell stack, plays a decisive role in the performance of the fuel cell stack. The membrane electrode is composed of the cathode and anode catalytic layers and the proton exchange membrane. The catalytic layer and the proton exchange membrane are the key components of the membrane electrode. , the catalytic layer plays the role of accelerating the oxygen reduction reaction, and the proton exchange membrane plays the role of isolating electrons and transporting protons. As a proton-conducting perfluorosulfonic acid polymer, the proton exchange membrane is heavily dependent on its Therefore, it is necessary to humidify the reaction gas to maintain a good hydration state of the proton e...

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Problems solved by technology

[0003] At present, most self-humidifying membrane electrode preparation technologies use hydrophilic inorganic oxides mixed with catalysts as the anode catalytic layer of the proton exchange membrane, and the cathode side uses hydrophobic inorganic oxides or PTFE mixed with catalysts as the cathode catalytic layer of the proton exchange membrane. For example, patents with publication numbers CN104716351A, CN103078122A and CN1750301A use TiO 2 , SnO 2 or W 2 o 3 Inorganic oxides are used as hydrophilic materials, but the addition of these inorganic oxides brings another serious problem. Since inorganic oxides are non-conductive electrons and protons, the addition of inorganic oxides seriously affects the membrane electrode. The proton transport performance increases the charge transfer resistance and ohmic resistance, which affects the performance of the battery. At the same time, the addition of hydrophilic inorganic oxides to the proton exchange membrane also seriously affects the mechanical properties of the proton exchange membrane.

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