Reversible superhydrophilic-superhydrophobic coating for fuel cell bipolar plates and method of making the same
View Patent ↗One variation may include a method which may include depositing a hydrophilic coating over at least a portion of a fuel cell bipolar plate. The bipolar plate may include a reactant gas header opening communication with the plurality of tunnels. Moreover, the tunnels may be communicating with a plurality of channels which may be defined by reactant gas flow field which may include a plurality of lands. At least a portion of the hydrophilic coating may be reacted with the material including a hydrophobic group which may provide a hydrophobic portion. Thereafter, at least a portion of the hydrophobic portion comprising oxidizing the hydrophobic group may be removed in order to regenerate the hydrophilic coating.
1. A method comprising:
depositing a hydrophilic coating over at least a portion of a fuel cell bipolar plate, the bipolar plate including a reactant gas header opening communicating with a plurality of tunnels, the tunnels communicating with a plurality of channels defined by a reactant gas flow field including a plurality of lands, reacting a portion of the hydrophilic coating with a material including a hydrophobic group, to provide a hydrophobic portion, and thereafter removing at least a portion of the hydrophobic portion comprising oxidizing the hydrophobic group to regenerate the hydrophilic coating and wherein the reaction may be a chemical or physical reaction.
2. A method as set forth in claim 1 wherein the hydrophilic coating comprises a metal oxide.
3. A method as set forth in claim 1 wherein the hydrophilic coating comprises titanium oxide.
4. A method as set forth in claim 1 wherein the hydrophobic material comprises a hydrophobic alkyl group.
5. A method as set forth in claim 1 wherein the hydrophobic material comprises n-octadecylsilane.
6. A method as set forth in claim 1 wherein the reaction product hydrophilic coating and the material including a hydrophobic group comprises a material having the formula of the Ti—O—Si—R, where R is a hydrophobic alkyl group.
7. A method as set forth in claim 1 wherein oxidizing comprises using UV radiation.