Fiber-shaped Zn-ion capacitors (FSZICs) have shown great potential in wearable electronics due to their long cycle life, high energy density, and good flexibility. Nevertheless, it is still a critical challenge to develop a conductive fiber with long size and high mechanical properties as the FSZIC cathode using sustainable and low-cost materials. Herein, regenerated cellulose (RC) -based conductive microfibers are prepared by a simple, continuous, and scalable wet spinning process. The 3D nanoporous networks of RC caused by physical self-cross-linking allow MXene and MnO(2) to be uniformly an...