Riveted microstructure induced by macro-modulation for reinforcing the potassium ion storage performance of metal sulfide

Abstract

Typically, general heterostructure easily generates accumulated interior stress at the interface of heterogeneous phases, which will deteriorate the potassium ion storage performance. Macro-control design improving microstructure stability is a promising construction strategy for obtaining high-performance anode materials. Herein, the spherical framework constituted by numerous nanograins has been fabricated for enhancing the electrochemical performance of the hetero-phase of ZnS combined with GeS₂ (ZGS-SP). Specially, the framework of ZGS-SP materials constituted by nanospheres delivers multiple cross-linked nodes, which can effectively disperse the inner stress, thereof improving the structure stability of primary grains. Meanwhile, due to the presence of the acting and reacting force and surficial carbon, the nanospheres can support each other as the framework structure expands in volume during K-ion insertion, thus heightening the structure tolerance of overall framework. As expected, the ZGS-SP materials express a prominent cycling stability (121.6 mAh g⁻¹ at 1 A g⁻¹ over 1000 cycles).