Multiscale Dot‐Wire‐Sheet Heterostructured Nitrogen‐Doped Carbon Dots‐Ti 3 C 2 T x /Silk Nanofibers for High‐Performance Fiber‐Shaped Supercapacitors

Fiber-shaped supercapacitors (FSCs) have become one of the significantly strategical flexible energy-storage materials towards future wearable textile electronics and metaverse technologies. Here, we develop the high-performance FSCs based on multiscale dot-wire-sheet heterostructure microfiber of nitrogen-doped carbon dots-Ti3C2Tx/silk nanofibers (NCDs-Ti3C2Tx/SNFs) hybrids via microfluidic fabrication. Due to the enlarged interlayer spacing, plentiful porous channels, accelerated H+ ion transport dynamics, large electrical conductivity and excellent mechanical strength/flexibility, the NCDs-Ti3C2Tx/SNFs possesses high volumetric capacitance (2218.7 F cm−3) and reversible charge–discharge stability in 1 M H2SO4 electrolyte. Furthermore, the solid-state FSCs present high energy density (57.9 mWh cm−3), good capacitance (1157 F cm−3), long-life cycles (82.3 % capacitance retention after 40000 cycles), which realize the actual energy-supply applications (powering lamp, watch and toy car).