Microfluidic Fabrication of Hierarchical-Ordered ZIF-L(Zn)@Ti3 C2 Tx Core-Sheath Fibers for High-Performance Asymmetric Supercapacitors.

ABSTRACT

We report hierarchical-ordered ZIF-L(Zn)@Ti3 C2 Tx MXene core-sheath fibers, in which a ZIF-L(Zn) nanowall array sheath is grown vertically on an anisotropic Ti3 C2 Tx core by Ti-O-Zn/Ti-F-Zn chemical bonds. Through highly efficient microfluidic assembly and microchannel reactions, ZIF-L(Zn)@Ti3 C2 Tx exhibits well-developed micro-/mesoporosity, ordered ionic pathways, fast interfacial electron conduction and large-scale fabrication, significantly boosting charges dynamic transport and intercalation. The resultant ZIF-L(Zn)@Ti3 C2 Tx fiber presents large capacitance (1700 F cm-3 ) and outstanding rate performance in a 1 M H2 SO4 electrolyte. Additionally, ZIF-L(Zn)@Ti3 C2 Tx fiber-based solid-state asymmetric supercapacitors deliver high energy density (19.0 mWh cm-3 ), excellent capacitance (854 F cm-3 ), large deformable/wearable capabilities and long-time cyclic stability (20 000 cycles), which realize natural sunlight-induced self-powered applications to drive water level/earthquake alarm devices.