Preparation of MXene Conductive Paper Based on Commercial Paper and Its Multifunctional Applications in Flexible Electronics

The growing demand for lightweight, low-cost, and mechanically compliant electronics has stimulated the development of paper-based conductive materials. MXene is a promising coating material for this purpose because of its metallic conductivity, hydrophilic surface terminations, and solution processability. However, in most MXene-coated paper systems, the relationship between coating thickness, microstructural evolution, and coupled functional performance remains insufficiently clarified. Herein, Ti 3 C 2 T x MXene was blade-coated onto commercial A4 paper to fabricate conductive papers with nominal coating thicknesses from 5 to 25 μm. This work uses the coating gap as a structural variable to clarify how the evolution from discontinuous fiber-supported MXene nanosheet coverage to a continuous lamellar conductive network regulates electron transport, Joule heating, electromagnetic interference (EMI) shielding, infrared shielding, and solar-driven evaporation. As the coating thickness increased from 5 to 25 μm, the sheet resistance decreased from 18 to 5.7 Ω sq −1, the equilibrium temperature under 5 V increased from approximately 33 to 61 °C, and the EMI shielding effectiveness (EMI SE) increased from 11.2 to 33.5 dB. The evaporation rate was also enhanced with increasing MXene loading. These improvements originate from increased inter-sheet contacts, reduced interfacial resistance, enhanced heat localization, and stronger attenuation of electromagnetic and infrared radiation. Compared with dense self-standing MXene films, the present MXene conductive paper emphasizes low-cost commercial paper substrates, scalable coating fabrication, mechanical flexibility, and multifunctional integration. This study clarifies a coating-gap-dependent structure−property relationship and provides practical guidance for the design of paper-based flexible electronic materials.