Synergistic promotion of sound absorption high-temperature stability and moisture resistance for SiO₂/C/SiBOC ceramic composites

Addressing the challenges associated with noise pollution problem necessitates the development of composite materials exhibiting both sound absorption and fire resistance under extreme environmental conditions. Conventional foam materials are limited by inadequate heat resistance, insufficient moisture resistance, and suboptimal functionality, rendering them unsuitable for such harsh environments. A new SiO 2 /C/SiBOC ceramic matrix porous sound-absorbing material was fabricated through a combination of sol-gel process, electrospinning, and organic impregnation techniques. Polyurethane foam (PUF) served as a template to establish a porous structure, while the SiBOC ceramic matrix conferred high-temperature resistance, and SiO 2 /C fiber reinforced the mechanical properties. Compared to traditional sound-absorbing materials, the developed composite demonstrates efficient sound absorption at low frequencies (NRC = 0.46) and across a broad frequency range (25–6500 Hz, α > 0.8). Additionally, it exhibits excellent thermal stability at elevated temperatures (up to 1400 °C), low thermal conductivity at room temperature (0.03463 W/m·K), high compressive strength (2.21 MPa), superior moisture resistance (contact angle θ = 101.4°), and a lightweight structure. This study contributes by proposing and validating a new design concept for porous ceramic composites, which can simultaneously balance acoustic, thermal, and mechanical properties as well as moisture resistance, effectively filling the gap in application areas of existing material systems.