Feng Zhen, Ma Yaqiang, Li Yi, Li Renyi, Liu Jing, Li Huiting, Tang Yanan, Dai Xianqi
College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007, People's Republic of China. College of Materials Science and Engineering, Henan Institute of Technology, Xinxiang, Henan 453000, People's Republic of China.
J Phys Condens Matter. 2019 Nov 20;31(46):465201. doi: 10.1088/1361-648X/ab3350. Epub 2019 Jul 18.
Exploring metal-free electrocatalysts with high efficiency and lower cost for oxygen reduction reaction (ORR) is necessary to realize the commercialization of fuel cells. In this paper, the ORR mechanisms on nitrogen-doped graphdiyne (GDY) are investigated using the first principles calculations. It is found that the GDY doped with sp-hybridized N at acetylenic sites can activate molecular oxygen (O). The kinetically most favorable reaction pathway is O → OOH → O + HO → OH → HO, which is an efficient four-electron ORR process. The first reaction step O → OOH is the rate determining step (RDS), and the energy barrier is 0.61 eV. The energy barrier of RDS is smaller than that of pure Pt (0.80 eV). Therefore, these results illustrate that sp-hybridized N-doped GDY is a promising carbon-based metal-free ORR catalyst.
探索用于氧还原反应（ORR）的高效且低成本的无金属电催化剂对于实现燃料电池的商业化是必要的。本文采用第一性原理计算研究了氮掺杂石墨炔（GDY）上的ORR机理。研究发现，在炔键位点掺杂sp杂化N的GDY可以活化分子氧（O）。动力学上最有利的反应途径是O→OOH→O + HO→OH→HO，这是一个高效的四电子ORR过程。第一步反应O→OOH是速率决定步骤（RDS），能垒为0.61 eV。RDS的能垒小于纯Pt的能垒（0.80 eV）。因此，这些结果表明，sp杂化N掺杂的GDY是一种有前景的碳基无金属ORR催化剂。
