Multiscale Dot‐Wire‐Sheet Heterostructured Nitrogen‐Doped Carbon Dots‐Ti3C2Tx/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-Ti₃ C₂ T_x /silk nanofibers (NCDs-Ti₃ C₂ T_x /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-Ti₃ C₂ T_x /SNFs possesses high volumetric capacitance (2218.7 F cm^-3 ) and reversible charge-discharge stability in 1 M H₂ SO₄ 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).