Flash Joule carbothermal chemistry to synthesize porous silica-based ceramics for thermal safety

Porous silica-based ceramics (PSCs) are widely utilized in diverse fields such as 5G smart devices, biomedicine, insulation, catalysis, and energy storage. Traditional methods for producing PSCs, such as sol-gel processes, sacrificial templates, chemical foaming, and solution spinning, are hampered by high temperatures, lengthy procedures, and complex steps, leading to significant energy consumption and environmental pollution. A novel Joule carbothermal chemistry technique has been developed for the rapid synthesis of porous ceramics materials, creating high-quality PSCs within 20 s. The intrinsic mechanisms of in-situ structural evolution and porosity formation were thoroughly studied. The resulting PSCs demonstrate exceptional thermal insulation properties, forming an effective thermal barrier that maintained a backside temperature as low as 63 °C when the front side was exposed to a 1300 °C flame. Additionally, various application scenarios for these PSCs are highlighted, notably improving the fire resistance and thermal insulation of lithium-ion batteries, thus paving the way for expanded ceramic production and broader applications.