Boosting CO₂ reduction on Fe-N-C with sulfur incorporation: Synergistic electronic and structural engineering

Journal Article · 05 December 2019 · Nano Energy

DOI: https://doi.org/10.1016/j.nanoen.2019.104384 · OSTI ID:1604622

Pan, Fuping ^[1]; Li, Boyang ^[2]; Sarnello, Erik ^[3]; Hwang, Sooyeon ^[4]; Gang, Yang ^[1]; Feng, Xuhui ^[1]; Xiang, Xianmei ^[1]; Adli, Nadia Mohd ^[5]; Li, Tao ^[6]; Su, Dong ^[4]; Wu, Gang ^[5]; Wang, Guofeng ^[2]; Li, Ying ^[1]

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1. Texas A & M Univ., College Station, TX (United States)
2. Univ. of Pittsburgh, PA (United States)
3. Northern Illinois Univ., DeKalb, IL (United States)
4. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
5. Univ. at Buffalo, NY (United States)
6. Northern Illinois Univ., DeKalb, IL (United States); Argonne National Lab. (ANL), Lemont, IL (United States)

Developing earth-abundant efficient catalysts for CO₂ reduction reaction (CO₂RR) is of paramount importance for electrochemical conversion of CO₂ into value-added products. Despite numerous studies on iron and nitrogen codoped carbon (Fe-N-C) catalysts, grand challenges exist due to limited performance and understanding of catalytic mechanisms. This study reports a general strategy to boost electrocatalytic CO₂RR activity of Fe-N-C with the incorporation of S atoms to engineer carbon support structure and electronic properties of active Fe-N sites simultaneously via a copolymer-assisted synthetic approach. The employment of N,S comonomers significantly increases the numbers of micropores and surface area, enabling dense atomic Fe-N and enhanced utilization efficiency. We report the first-principles calculations reveal that S modulation upraises the Fermi energy of Fe 3d and increases charge density on Fe atoms of Fe-N₄, thereby enhancing intrinsic catalytic reactivity and selectivity for CO₂ reduction by strengthening the binding interaction between the Fe site and key COOH* intermediate. These integrated structural and electronic merits endow Fe-NS-C with outstanding activity (e.g., CO Faradaic efficiency of 98% at an overpotential of 490 mV) and stability (without deactivation in 30 h), ranking it one of the most active Fe-N-C reported to date. The finding offers an innovative design strategy to enable the design of advanced catalysts for CO₂ conversion.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States); Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
• Grant/Contract Number: SC0012704; AC02-06CH11357
• OSTI ID: 1604622
• Alternate ID(s): OSTI ID: 1615906; OSTI ID: 1694278
• Report Number(s): BNL--213731-2020-JAAM
• Journal Information: Nano Energy, Journal Name: Nano Energy Journal Issue: C Vol. 68; ISSN 2211-2855
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English