Water-retaining anode structure for a fuel cell
A novel anode structure for making a proton exchange membrane fuel cell (PEMFC) tolerant to incidences of cell reversal includes an electrocatalyst layer having at least one electrocatalyst and at least one proton conducting polymer. The anode structure also includes one or more water retaining material(s), such as carbon nanofibers, embedded within the electrocatalyst layer.
1. An anode structure for making a proton exchange membrane fuel cell (PEMFC) tolerant to incidences of cell reversal, said anode structure comprising an electrocatalyst layer wherein said electrocatalyst layer comprises at least one electrocatalyst, at least one proton conducting polymer, and carbon nanofibres, and wherein the at least one electrocatalyst is supported on macroscopic conductive carbon particles.
2. An anode structure according to claim 1 , wherein the nanofibres have a diameter in the range of 10 nanometers to 100 nanometers.
3. An anode structure according to claim 2 , wherein the nanofibres have an average length of 1 micron to 100 microns.
4. An anode structure according to claim 3 , wherein the nanofibres have an aspect ratio in the range of from 5 to 1000.
5. A membrane electrode assembly comprising an anode structure according to claim 1 .
6. A proton exchange membrane fuel cell comprising an anode structure according to claim 1 .
7. A proton exchange membrane fuel cell comprising a membrane electrode assembly according to claim 5 .
8. An anode structure according to claim 1 , wherein the nanofibres are nanotubes.
9. An anode structure according to claim 8 , wherein the nanotubes consist of a series of graphitic sheets wrapped around a hollow core.