Simultaneously Engineering the Coordination Environment and Pore Architecture of Metal–Organic Framework‐Derived Single‐Atomic Iron Catalysts for Ultraefficient Oxygen Reduction. Issue 40 (8th September 2021)

• Record Type: Journal Article
• Authors: Liu, Feng; Shi, Lei; Song, Shaofeng; Ge, Kai; Zhang, Xiaopeng; Guo, Yingchun; Liu, Dong
• Is Part Of: Small. Volume 17:Issue 40(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-08
• Subjects: architectural engineering -- electronic structure modulation -- metal–organic frameworks -- oxygen reduction -- single‐atom Fe; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202102425
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Designing highly efficient and durable electrocatalysts that accelerate sluggish oxygen reduction reaction kinetics for fuel cells and metal–air batteries are highly desirable but challenging. Herein, a facile yet robust strategy is reported to rationally design single iron active centers synergized with local S atoms in metal–organic frameworks derived from hierarchically porous carbon nanorods (Fe/N, S‐HC). The cooperative trithiocyanuric acid‐based coating not only introduces S atoms that regulate the coordination environment of the active centers, but also facilitates the formation of a hierarchically porous structure. Benefiting from electronic modulation and architectural functionality, Fe/N, S‐HC catalyst shows markedly enhanced ORR performance with a half‐wave potential ( E 1/2 ) of 0.912 V and satisfactory long‐term durability in alkaline medium, outperforming those of commercial Pt/C. Impressively, Fe/N, S‐HC‐based Zn–air battery also presents outstanding battery performance and long‐term stability. Both electrochemical experimental and density functional theoretical (DFT) calculated results suggest that the FeN4 sites tailored with local S atoms are favorable for the adsorption/desorption of oxygen intermediate, resulting in lower activation energy barrier and ultraefficient oxygen reduction catalytic activity. This work provides an atomic‐level combined with porous morphological‐level insights into oxygen reduction catalytic property, promoting rational design and development of novel highly efficient single‐atom catalysts for the renewable energy applications. Abstract : Hierarchical porous carbon nanorods decorated with atomically dispersed FeN4 sites modulated by local S for oxygen reduction (ORR) are prepared. The simultaneously modified electron structure and pore architecture could provide superior intrinsic ORR activity and more three‐phase boundaries to facilitate the mass transport of ORR‐relevant species, which result in ultraefficient oxygen reduction in alkaline medium.