Hierarchically Porous M-N-C (M = Co and Fe) Single-Atom Electrocatalysts for Fuel Cells
Primary author: Zhaoyuan Lyu
Faculty sponsor: Yuehe Lin
Primary college/unit: Voiland College of Engineering and Architecture
The integration of hydrogen into power generation applications is critical for an environmentally friendly and sustainable energy pattern. Fuel cells are considered as one of the cleanest energy conversion technologies. The efficiency and cost of fuel cells, however, are still hurdled by the development of cost-effective catalysts that reduces oxygen at the cathode side. Currently, there is an intensive research effort for highly efficient electrocatalysts based on low-cost and earth-abundant elements. Improving non-precious metal catalysts require rational control over their size, shape, composition, and structure. In particular, single-atom catalysts (SACs) show great promise owing to their high catalytic activity, stability, selectivity, and 100?% atom utilization. Through innovative synthesis methods, we have developed a universal strategy to design and construct hierarchically porous SACs with highly active sites, MN2 (M = Fe or Co), which outperform the commercial precious-metal catalysts and show great potential for practical proton-exchange membrane fuel cells. Combining advanced characterization techniques and theoretical simulation, we further unravel the origin of the high catalytic activity of SACs at the atomic level. The findings shed light on the catalytic reaction mechanism of SACs and may help future development of low-cost and highly efficient fuel cell catalysts.