Constructing 2D Sandwich‐like MOF/MXene Heterostructures for Durable and Fast Aqueous Zinc‐Ion Batteries

Two‐dimensional metal–organic frameworks (2D MOFs) can be used as the cathodes for high‐performance zinc‐ion battery due to their large one‐dimensional channels. However, the conventionally poor electrical conductivity and low structural stability hinder their advances. Herein, we report an alternately stacked MOF/MX heterostructure, exhibiting the 2D sandwich‐like structure with abundant active sites, improved electrical conductivity and exceptional structural stability. Ex situ characterizations and theoretical calculations reveal a reversible intercalation mechanism of zinc ions and high electrical conductivity in the 2D heterostructure. Electrochemical tests confirm excellent Zn2+ migration kinetics and ideal pseudocapacitive behaviors. As a consequence, Cu‐HHTP/MX shows a superior rate performance (260.1 mAh g−1 at 0.1 A g−1 and 173.1 mAh g−1 at 4 A g−1) and long‐term cycling stability of 92.5 % capacity retention over 1000 cycles at 4 A g−1. A MOF/MXene heterostructure, which exhibits a molecular‐scale hybridized MOF (Cu‐HHTP) and MX (V2CTx MXene) nanosheets, is successfully synthesized. The results show that the Zn2+ storage capability of such a 2D heterostructure is boosted by enhancing the structural stability, electrical conductivity, and the utilization of active sites.