Al-zigzag-SiNT (9, 0), Al-armchair-SiNT (5, 5) and Al-chiral-SiNT (9, 3) as catalysts with high efficiency to oxygen reduction reaction in fuel cells

Abstract

In recent years due to high usage of fuel cells, the development of novel catalysts to oxygen reduction reaction (ORR) with high efficiency is a fundamental principle. In current study, in acidic environment the performance of Al-zigzag-SiNT (9, 0), Al-armchair-SiNT (5, 5) and Al-chiral-SiNT (9, 3) to ORR were studied by theoretical models. Possible pathways for ORR on Al-zigzag-SiNT (9, 0), Al-armchair-SiNT (5, 5) and Al-chiral-SiNT (9, 3) via Eley-Rideal (ER) and Langmuir-Hinshelwood (LH) were examined. The optimal mechanism to ORR on Al-zigzag-SiNT (9, 0), Al-armchair-SiNT (5, 5) and Al-chiral-SiNT (9, 3) from thermodynamic view point was proposed. The overpotential values on Al-zigzag-SiNT (9, 0), Al-armchair-SiNT (5, 5) and Al-chiral-SiNT (9, 3) surfaces are 0.34, 0.36 and 0.39 V, respectively. The calculated overpotential are lower than overpotential on platinum-based catalysts (0.45 V). Finally, the Al-zigzag-SiNT (9, 0) can be proposed as catalysts to ORR with high performance.