Innovative strategies for designing and constructing efficient fuel cell electrocatalysts

Abstract

Polymer electrolyte membrane fuel cells (PEMFCs) are one of the most promising energy conversion devices due to their high efficiency and zero emission, however, two major challenges, high cost and short lifetime, have been hindering the commercialization of fuel cells. Achieving low-Pt or non-precious metal oxygen reduction reaction (ORR) electrocatalysts is one of the main research ideas in this field. In this review, the degradation mechanism of Pt-based catalysts was firstly explained and elucidated, and then three strategies were suggested for the reduction of Pt usage without loss of activity and durability: alloy structured low-Pt electrocatalysts, core-shell or hollow structured low-Pt electrocatalysts, and multi-size synergistic effect low-Pt catalysts. For carbon-based non-precious metal catalysts, the problems and challenges faced by heteroatom/transition-metal doped carbon-based catalysts are concluded, and several strategies to improve the activity of heteroatom/transition-metal doped carbon catalysts are suggested. Particularly, an innovative quantum well catalyst structure reported quite recently was presented which may open up new prospects for the development of fuel cell technology. Finally, this review concludes with a brief conclusions and prospects for future development of low-Pt and non-precious metal fuel cell electrocatalysts.