Work

How the curvature-rich structure of N-doped graphene enables asymmetric polysulfide redox catalysis for highly promising Li–S batteries

Year: 2025

Type: article

Abstract: The catalytic conversion of polysulfides remains a critical bottleneck in the development of high-performance lithium–sulfur batteries (LSBs). Despite extensive efforts to engineer carbon-based materials for LSBs, such as nitrogen (N)-doped graphene, the intrinsic limitations of conventional N-doped configurations have hindered catalytic effectiveness. Here, we reveal how the curvature-rich structure of N-doped graphene (N-CR-G) regulates catalytic properties to promote the sulfur reduction reaction (SRR). This architecture induces a diversity of active N configurations and optimizes the local electronic structure, directly accelerating the polysulfide redox kinetics. Unlike conventional carbon-based materials, the main N-doped configuration of N-CR-G catalyzes an uncommon asymmetric reaction pathway involving the rapid generation of soluble radicals, effectively suppressing the accumulation of insoluble Li 2 S 2 intermediates and enhancing sulfur utilization. While the curvature structure also facilitates carbon vacancy formation and enables room-temperature N doping, its primary contribution lies in tailoring the catalytic landscape of graphene. This work underscores the significance of curvature engineering for activating and regulating electrocatalytic behavior, offering a powerful strategy to design advanced cathode materials for highly promising LSBs. • Curvature-engineered N-doped graphene with multi-configurational active sites was developed, enabling synergistic enhancement of polysulfide adsorption and asymmetric redox catalysis in Li–S batteries. • The design accelerates sulfur conversion via the -mediated pathway, suppresses Li 2 S 2 accumulation, and achieves exceptional cycling stability (<0.05% decay per cycle), surpassing conventional N-doped graphene. • Theoretical and experimental analyses reveal curvature-induced electronic modulation and doping facilitation, clarifying the origin of the superior areal capacity and long-term cyclability.

Source: eScience

DOI: 10.1016/j.esci.2025.100496