Fabrication of Advanced Energy Materials
Lee, J.K., Anderson, G., Tricker, A.W., Babbe, F., Madan, A., Cullen, D.A., Arregui-Mena, J.D., Danilovic, N., Mukundan, R., Weber A.Z., Peng, X. (2023) Ionomer-free and recyclable porous-transport electrode for high-performing proton-exchange-membrane water electrolysis. Nature Communications 14, 4592.
Our new electrode operates in absence of ionomer being present in the anode compartment! Not only does it reduce the number of processes required for fabrication, but also enables facile recycling of electrodes, porous transport layers and membranes. The ionomer-free porous transport electrodes demonstrate a voltage reduction of > 600 mV compared to conventional ionomer-coated porous transport electrodes at current density of 1.8 A/cm2 and < 0.1 mgIr/cm2, and a voltage degradation of 29 mV at average rate of 0.58 mV per 1000-cycles after 50k cycles of accelerated-stress tests at 4 A /cm2.
Lee, J.K., Lee, CH., Fahy, K.F., Kim, P.J., Krause, K., LaManna, J.M., Baltic, E., Jacobson, D.L., Hussey, D.S., Bazylak, A. (2020) Accelerating Bubble Detachment in Porous Transport Layers with Patterned Through-Pores. ACS Applied Energy Materials.
The engineering of patterned through-pores (PTPs) on commercial titanium porous transport layers (PTLs) immensely reduced mass transport losses experienced in PEM water electrolyzers. The by-product gas was effectively removed via PTPs, which enhanced the electrolyzer efficiency at high current densities (up to 9 A/cm2). The gas breakthrough event for a commercial PTL occurred over 10 seconds while the gas breakthrough event for PTP PTL occurred within a second (refer to video).
Commercial PTL
PTP PTL
Lee, J.K., Lee, CH., Fahy, K.F., Kim, P.J., LaManna, J.M., Baltic, E., Jacobson, D.L., Hussey, D.S., Stiber, S., Gago, A.S., Friedrich, K.A., and Bazylak, A. (2020) Elucidating Multiphase Flow Behaviour in Spatially Graded Porous Transport Layers for High Performance Polymer Electrolyte Membrane Electrolyzers. Energy Conversion and Management.
A novel, spatially graded porous transport layer was fabricated to improve effective reactant and product transport in PEM electrolyzers. The impact of the porosity gradient direction (with either high porosity to low porosity or low porosity to high porosity from the reaction site to the exhaust) was studied using pore network modeling and operando neutron imaging. The results of the study showed that positioning a lower porosity near the reaction sites (i.e., adjacent to the catalyst layer) significantly reduced both ohmic losses and mass transport losses.
