MOF and MOF-derived composites for flexible energy storage devices

With the rapid development of wearable electronic devices and smart medical care, flexible energy storage has ushered in an unprecedented development. The new material metal-organic framework (MOF) is composed of metal ions and organic ligands through coordination, and has been widely studied for its highly adjustable structure, large specific surface area and the ability to adapt to electrode deformation during charging and discharging. However, pristine MOF usually suffers from the poor conductivity, and the unsatisfied stability during long cycles which restricts its practical application. Herein, we focus on the strategies to solve the problems, including optimizing structures, combing with conductive materials and obtaining MOF-derived materials. In this review, the classification of MOF-based electrodes, together with the improving methods and synthesis steps, are totally discussed. Furthermore, the overall electrochemical performances and flexibility of devices are presented in detail. Based on the performances, major challenges and perspectives of MOF are also proposed for next-generation flexible energy storage devices.