Hierarchical MXene/ZnO Nanorods: WO₃/CNT Trilayer Coatings on Cotton for High-Performance Multifunctional Wearable Fabrics

Fabric-based wearable electronics are gaining increasing attention owing to their flexibility, breathability, biocompatibility, and seamless integration into clothing. However, most existing studies rely primarily on metallic or carbon-based conductive materials. In contrast, the integration of semiconducting metal oxides in wearable textiles remains limited, despite their advantages in achieving tunable electrical and thermal responses. In this study, we developed a sandwich-structured coating on cotton fabric, where a semiconductive layer of WO₃-doped ZnO nanorods was embedded between two conductive layers of MXene and carbon nanotubes (CNTs). This hierarchical and heterogeneous coating architecture enabled synergistic interactions that significantly enhance multifunctional performance. The engineered fabric exhibited reliable strain sensing with a short response and recovery time (∼200 ms), excellent mechanical durability over 2000 stretch/release cycles, and the ability to monitor human motion. Furthermore, the fabric demonstrated efficient Joule heating, reaching ∼110°C within ∼15 s, and high electromagnetic interference (EMI) shielding effectiveness (∼34.4 dB), which increased to ∼78 dB by raising fabric thickness, meeting commercial EMI standards. Notably, these functionalities were achieved without compromising flexibility, light weight, and breathability. Thus, this study presents a new paradigm for designing multifunctional textile electronics by integrating semiconductive and conductive nanomaterials, overcoming the limitations of conventional conductive-only approaches.