Delicately aligned structures of two-dimensional (2D) MXene nanosheets have demonstrated positive effects on applications, especially in electromagnetic interference (EMI) shielding and infrared (IR) stealth. However, precise regulation of structural assembly by theory-guided solution processing is still a great challenge. Herein, one-dimensional (1D) cellulose nanofibers (CNFs) with a high aspect ratio are applied as a reinforcing agent and a rheological modifier for MXene/CNF colloids to fabricate aligned MXene-based materials for EMI shielding and IR stealth. Notably, a systematical rheological study of the MXene/CNF colloids is proposed to determine the optimal solution-processing conditions for finely oriented component arrangement requirements and provides in-depth information on the interactions between the components. The delicately regulated orientation structure assembled by shear inducement is convincingly demonstrated through micro-CT and wide-angle X-ray diffraction/small-angle X-ray scattering (WAXD/SAXS), which endows the MXene/CNF film with a significantly enhanced electrical conductivity of 46 685 S m–1, a tensile strength of 281.7 MPa, and Young’s modulus of 14.8 GPa. Furthermore, the highly aligned structure of the ultrathin film possesses a great enhancement in EMI shielding effectiveness (50.2 dB) and IR stealth (0.562 emissivity). These findings provide a fruitful understanding of the optimized fabrication in solution processing of high-performance MXene-based functional composite films and open up a great opportunity for the development of multifunctional stealth materials.

Nitroxide radicals have fast and reversible redox reactions and high electron transfer rates, while the instability in electrolytes and low conductivity restrict their applications on electrodes. Here, we employ two-dimensional MXene Ti 3 C 2 T x as a conductive film-forming agent for 4-amino-TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidine-1-oxyl) to prepare a freestanding and flexible electrode. Pendant nitroxide radicals experience two-electron storage through reversible redox reactions and realize synergistically boosted charge storage with redox-active Ti 3 C 2 T x nanosheets. A systematic electrochemical investigation demonstrates that nitroxide radicals greatly contribute to the surface capacitance of the hybrid electrode, which significantly improves its diffusion-capacitive dualmodel energy storage and cycling stability. Further, the assembled symmetric supercapacitor achieves a high energy density of 60.3 Wh kg −1 and the all-in-one asymmetric supercapacitor shows a wide potential window of 1.8 V, demonstrating great promise in energy storage devices.