Synergistic effect of adsorption and electrocatalysis of ZnO@MnO2 PCNFs for high-performance lithium-sulfur batteries

Abstract

Catalytic conversion is a new strategy to mitigate the shuttle effects of lithium-sulfur batteries, but the catalyst must play an effective role in both oxidation and reduction processes. In this paper, a lotus root-like ZnO@MnO2 PCNFs with a built-in electric field are proposed as cathodes for lithium-sulfur batteries. Due to the synergistic effect of both components, ZnO@MnO2 PCNFs demonstrated outstanding bidirectional catalytic performance, with ZnO primarily enhancing catalysis and MnO2 regulating adsorption. The ZnO@MnO2 PCNFs exhibit higher initial capacity (1582 mAh g−1 at 0.1 C), and longer cycle life (2000 cycles with 0.023 % decay per period at 2 C). Even under high S loading of 8.32 mg cm−2 and a low electrolyte to sulfur ratio is about 4.8 μL mg−1, the cell with ZnO@MnO2 PCNFs shows a discharge capacity of 688.6 mAh g−1 at 0.2 C, and maintained at 420.9 mAh g−1 after 100 cycles. This approach has shown promise in improving the efficiency and cycling stability of Li-S batteries, making them more viable for practical applications.