Anchoring Metal‐Organic Framework‐Derived ZnTe@C onto Elastic Ti3C2Tx MXene with 0D/2D Dual Confinement for Ultrastable Potassium‐Ion Storage

Abstract

AbstractThe prosperous deployments of renewable energy have stimulated the looming exploration of K‐ion batteries (KIBs) for grid‐scale energy storage because of their high energy density and low cost. However, lacking advanced anode materials with high theoretical capacity, fast K+ storage kinetics, and eco‐friendliness discourages KIB development. Here, for the first time, ZnTe as an advanced KIB anode material with a conversion reaction mechanism (yZnTe + xK+ + xe− → yZn + KxTey) is demonstrated. The ZnTe nanoparticles are uniformly dispersed in a carbon matrix using metal–organic frameworks as starting materials, which are subsequently anchored on Ti3C2Tx MXene nanosheets, forming elaborate ZnTe@C/Ti3C2Tx (ZCT) nanohybrids. Various theoretical modeling and postmortem examinations reveal the synergistic integrations between carbon and Ti3C2Tx. Compositionally, they regulate the electronic structure of ZnTe, providing fast K+ adsorption kinetics. Morphologically, they construct a 0D/2D dual confinement, addressing the volume change of ZnTe upon cycling. Therefore, the ZCT exhibits a high capacity (408.0 mA h g−1 at 0.1 A g−1) and excellent long‐term cyclability (230.2 mA h g−1 at 1.0 A g−1 after 3500 cycles), outperforming other reported transition‐metal‐chalcogenides. Significantly, the ZCT‐based full cells achieve a high energy density of 110.3 Wh Kg−1, making ZCT promising for practical applications.