Characterization and thermal insulation of Mg(-Al/Zr)-Si oxide fibers prepared by dual-source precursor of magnesium citrate complex combined with chlorides

Ceramic fibers have emerged as a promising candidate for advanced thermal insulation applications due to their exceptional thermomechanical properties and chemical resistance. In this work, Mg(-Al/Zr)-Si ceramic fibers were successfully prepared via electrospinning technology using a dual-source precursor strategy, combining magnesium citrate complex and metal chlorides as metal oxides precursors. The crystalline phase formation, thermal decomposition behavior, microstructure, and properties of the fibers were systematically investigated using X-ray diffraction (XRD), thermogravimetric-differential scanning calorimetry (TG-DSC), Fourier transform infrared spectroscopy (FT–IR), and scanning electron microscopy (SEM). The heterogeneous sol precursor notably influenced the fiber crystallization process and facilitated more gradual thermal decomposition, as evidenced by reduced weight loss rates. Consequently, the Mg(-Al/Zr)-Si ceramic fibers maintained good structural integrity after exposure to 1200 °C. Moreover, the incorporation of aluminum or zirconium enhanced the tensile strengths of fibers (heat treated at 800 °C) to 1.56–1.79 MPa, representing a significant improvement over pure magnesium silicate fibers. Furthermore, the fibers exhibited good thermal insulation performance with low room-temperature thermal conductivity values ranging from 0.0282 to 0.0333 W·m −1 ·K −1 , further highlighting their suitability for high-temperature insulation applications. These findings underscore the significant potential of the developed fibers for use in high temperature thermal management and insulation systems.