High-strength, electrochemically efficient RuO2-MXene/CNTs hybrid fibres via nanostructure design for flexible electronics and energy storage

Demand for smart textiles in wearables spotlights MXene fibres, but their use is limited by mechanical robustness, electrochemical activity, and electrical stability challenges. In this paper, a three-dimensional network-structured hybrid fibre with high tensile strength, flexibility, electrical conductivity, and superior electrochemical characteristics was successfully fabricated by combining hydrothermal synthesis and wet-spinning techniques. Initially, an in-situ hydrothermal method was used to uniformly anchor hydrated RuO 2 nanoparticles onto MXene nanosheets. These RuO 2 -MXene composites were subsequently combined with carbon nanotubes (CNTs) to construct RuO 2 -MXene/CNTs hybrid fibres via a wet-spinning process. RuO 2 prevents MXene re-lamination and adds pseudocapacitance, improving ion access and charge storage. Meanwhile, CNTs create a strong 3D conductive network, boosting charge transport and mechanical strength. As a result, the RuO 2 -MXene/CNTs hybrid fibres achieved a superior specific volumetric capacitance reaching 77.9F/cm 3 , along with outstanding cyclic stability, maintaining 88.1 % of the capacitance after 1000 charge–discharge operations. Additionally, the hybrid fibres displayed outstanding flexibility and electrical stability, with a resistance variation of less than 0.7 % under continuous rapid bending over 8000 s. These findings clearly demonstrate that RuO 2 -MXene/CNTs hybrid fibres possess high potential for application as electrode materials in the domain of future flexible electronics.