Wu Zhen, Liu Mingliang, He Wenfeng, Guo Tong, Tong Wei, Kan Erjun, Ouyang Xiaoping, Qiao Fen, Wang Junfeng, Sun Xueliang, Wang Xin, Zhu Junwu, Coskun Ali, Fu Yongsheng
Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education, Nanjing University of Science and Technology, Nanjing, China.
School of Energy and Power Engineering, Jiangsu University, Zhenjiang, China.
Nat Commun. 2024 Nov 4;15(1):9535. doi: 10.1038/s41467-024-53797-y.
Electrocatalysts are extensively employed to suppress the shuttling effect in lithium-sulfur (Li-S) batteries. However, it remains challenging to probe the sulfur redox reactions and mechanism at the electrocatalyst/LiPS interface after the active sites are covered by the solid discharge products LiS/LiS. Here, we demonstrate the intrinsic autocatalytic activity of the LiS (100) plane towards lithium polysulfides on single-atom nickel (SANi) electrocatalysts. Guided by theoretical models and experimental data, it is concluded that LiPS dissociates into LiS and short-chain LiPS on the LiS (100) plane. Subsequently, LiS undergoes further lithiation to LiS on the LiS (100) surface, generating a new LiS (100) layer, thus enabling the autocatalytic formation of a new LiS (100) surface. Benefiting from the autocatalytic growth of LiS, the concentration of LiPS in the electrolyte remains at a lower level, enabling Li-S batteries under high loading and low electrolyte conditions to exhibit superior electrochemical performance.
电催化剂被广泛用于抑制锂硫（Li-S）电池中的穿梭效应。然而，在活性位点被固态放电产物LiS/LiS覆盖后，探究电催化剂/锂多硫化物（LiPS）界面处的硫氧化还原反应及机理仍然具有挑战性。在此，我们展示了LiS(100)面在单原子镍（SANi）电催化剂上对锂多硫化物的固有自催化活性。在理论模型和实验数据的指导下，得出LiPS在LiS(100)面上分解为LiS和短链LiPS的结论。随后，LiS在LiS(100)表面进一步锂化为LiS，生成新的LiS(100)层，从而实现新LiS(100)表面的自催化形成。受益于LiS的自催化生长，电解液中LiPS的浓度保持在较低水平，使高负载和低电解液条件下的Li-S电池表现出优异的电化学性能。
