Porous metal materials for polymer electrolyte membrane fuel cells - A review

Porous metals are very popular functional materials that have been used for various fields due to their attractive properties such as high porosity, controllable permeability, and high specific surface area, etc. This study provides an overall review of the fabrication, characterization and application of the porous metal materials (PMMs) for polymer electrolyte membrane fuel cell (PEMFC) applications. Metal foams, porous metal sinters, metal meshes and perforated metals are included. Such materials have been used as flow distributor/flow field, current collector, gas diffusion backing and also catalyst support. Different applications require different dominant characteristics of the PMMs. Although the feasibility of using the PMMs for PEMFC applications have been comprehensively validated by both modeling and experimental investigations, there still exists plenty of scope to explore the in-depth mechanisms concerning how and how much the PMMs contribute to the fuel cell performance. This work not only summarizes the development of this subject, but also analyzes the challenges that must be overcome in the future. Moreover, a systematical optimization link for active functional design (AFD) of PEMFC-oriented PMMs is also presented. (C) 2012 Elsevier Ltd. All rights reserved.