Recent Progress of <scp>MX</scp>ene‐Based Nanomaterials in Flexible Energy Storage and Electronic Devices

The increasing demands for wearable electronics have stimulated the rapid development of flexible energy storage devices. MX enes are considered as promising flexible electrodes due to the ultrahigh volumetric specific capacitance, metallic conductivity, superior hydrophily, and rich surface chemistry. This work reviews, for the first time, the recent advances of MX ene‐based nanomaterials in flexible energy storage devices, including pure MX enes, MX ene‐carbon composites, MX ene‐metal oxide composites, and MX ene‐polymer composites. Applications of MX enes in flexible electronics such as sensors, nanogenerators, and electromagnetic interference shielding are also included. Then, properties of stress, strain, conductivity, and capacitance are compared to help researchers to keep balance between mechanical and electrochemical performances in designing flexible devices. Finally, challenges together with the possible solutions related to the application of MX enes in flexible devices and outlook to future directions are provided.