Theoretical insights into the electroreduction of nitrate to ammonia on graphene-based single-atom catalysts

Yuanyuan Wang; Donghai Wu; Peng Lv; Bingling He; Xue Li; Dongwei Ma; Yu Jia

doi:10.1039/d2nr02813a

Theoretical insights into the electroreduction of nitrate to ammonia on graphene-based single-atom catalysts

Nanoscale. 2022 Aug 4;14(30):10862-10872. doi: 10.1039/d2nr02813a.

Authors

Yuanyuan Wang^{1

2}, Donghai Wu^{1

2

3}, Peng Lv^{1

2}, Bingling He^{1

2}, Xue Li^{1

2}, Dongwei Ma^{1

2}, Yu Jia^{1

2

4}

Affiliations

¹ Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng 475004, China. madw@henu.edu.cn.
² Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng 475004, China.
³ Henan Key Laboratory of Nanocomposites and Applications, Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou 450006, China.
⁴ International Laboratory for Quantum Functional Materials of Henan, and School of Physics, Zhengzhou University, Zhengzhou 450001, China.

PMID: 35843116
DOI: 10.1039/d2nr02813a

Abstract

Electrocatalytic reduction of harmful nitrate (NO₃^-) to valuable ammonia (eNO₃RR) is critical and attractive for both environmental remediation and energy transformation. A single atom catalyst (SAC) based on graphene represents one of the most promising eNO₃RR catalysts. However, the underlying catalytic mechanism and the intrinsic factors dictating the catalytic activity trend remain unclear. Herein, using first-principles calculations, eNO₃RR on TMN₃ and TMN₄ (TM = Ti-Ni) doped graphene was thoroughly investigated. Our results reveal that FeN₄ doped graphene exhibits excellent eNO₃RR performance with a low limiting potential of -0.38 V, agreeing with the experimental finding, which can be ascribed to the effective adsorption and activation of NO₃^-via the charge "acceptance-donation" mechanism and its moderate binding due to the occupation of the d-p antibonding orbital. In particular, we found that eNO₃RR activities are well correlated with the intrinsic properties of TM centers and their local environments. With the established activity descriptor, several other graphene-based SACs were efficiently screened out with excellent eNO₃RR performance. Our studies could not only provide an atomic insight into the catalytic mechanism and activity origin of eNO₃RR on graphene-based SACs, but also open an avenue for the rational design of SACs for eNO₃RR towards ammonia by regulating the metal center and its local coordination environment.