Emerging electrocatalysts for PEMFCs applications: Tungsten oxide as an example

Proton exchange membrane fuel cells (PEMFCs) is one of the most promising clean energy technologies in twenty-first century owing to its unique characters of high energy density, cleanability and silent operation, while its performance depends largely on the catalytic activity and durability. Tungsten oxide as a low-cost electrode catalytic material is attracting more and more attentions. In this perspective, we try to summarize the recent developments of WO_x-based electrode materials and its multifunctional roles as the acid-resisting support, catalyst, hydrogen reservoir, hydrogen supplier and oxygen scavenger in PEMFCs. Finally, the remaining challenges and promising avenues for efficiently developing WO₃ based catalysts towards large-scale application of PEMFCs are highlighted.