MOF for template-directed growth of well-oriented nanowire hybrid arrays on carbon nanotube fibers for wearable electronics integrated with triboelectric nanogenerators

An integrated self-charging power system incorporating flexible fiber-shaped coaxial asymmetric supercapacitors (FASCs) with flexible triboelectric nanogenerators (FTENGs) has the potential to harvest and store energy simultaneously for achieving self-charged power pack. In this study, we develops a new strategy for fabricating a metal-organic framework (MOF) for the template-directed growth of hierarchically well-oriented nanowire arrays based on carbon nanotube fibers (CNTFs) for electrochemical supercapacitors . Uniform CNTFs@ZnCo 2 O 4 @Zn-Co-S hybrid arrays (HAs) derived from a zinc/cobalt-based zeolitic imidazolate framework (Zn/Co-ZIF) are first fabricated via a facile annealing and sulfuration process and a CNTFs@H-Co 3 O 4 @CoNC HA derived from a Co-based MOF is synthesized via oxidation and carbonization processes ; the products act as positive and negative electrodes respectively in the assembled FASCs. The as-prepared CNTFs@ZnCo 2 O 4 @Zn-Co-S HAs and CNTFs@H-Co 3 O 4 @CoNC HAs are endowed with rich reaction sites, a facile ion diffusion path , and improved conductivity because of their unique hierarchical structure and good synergistic effect , which improves the electrochemical properties of the MOF derivatives. In addition, the assembled FASCs device exhibits a remarkable electrochemical performance with excellent rate capability. This study provides a strategy for the rational design of hierarchically structured, well-oriented MOFs and derivative arrays with high electrochemical performance and mechanical flexibility. Moreover, the flexible fiber-shaped MOF–derivative HA asymmetric supercapacitor is charged by a flexible triboelectric nanogenerator, demonstrating the promise of an self-charging power pack that has considerable potential for developing flexible multifunctional electronic devices.