Abstract
The prevalent catalysts for natural and artificial N2 fixation are known to hinge upon transition-metal (TM) elements. Herein, we demonstrate by density functional theory that Al-doped graphene is a potential non-TM catalyst to convert N2 to NH3 in the presence of relatively mild proton/electron sources. In the integrated structure of the catalyst, the Al atom serves as a binding site and catalytic center while the graphene framework serves as an electron buffer during the successive proton/electron additions to N2 and its various downstream NxHy intermediates. The initial hydrogenation of N2 can readily take place via an internal H-transfer process with the assistance of a Li+ ion as an additive. In view of the recurrence of H transfer in the first step of N2 reduction observed in biological nitrogenases and other synthetic catalysts, this finding highlights the significance of heteroatom-assisted H transfer in the design of synthetic catalysts for N2 fixation.
| Original language | English |
|---|---|
| Pages (from-to) | 570-576 |
| Number of pages | 7 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 9 |
| Issue number | 3 |
| DOIs | |
| State | Published - Feb 1 2018 |
Funding
This research was supported by the Faculty Startup Grant of Sichuan University and by the National Science Foundation of China (Grant No. 21443012). Part of the work was performed at the Center for Nanophase Materials Sciences (CNMS), which is a U.S. Department of Energy Office of Science User Facility. Y.-H.T. thanks the National Supercomputing Center in Shenzhen for providing the computational resources and Gaussian09 program (version of ES64LG09RevD. 01). J.J., B.G.S., and J.H. acknowledge resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DEAC02-05CH11231.