Solution blow spinning mass production of mullite nanofiber from environment friendly aqueous Al–Si solutions

Abstract

Achieving large-scale production of high-performance mullite ceramic nanofibers posed a formidable challenge. Herein, an air heating-solution blow spinning technique was designed for the mass fabrication of mullite nanofibers at high speeds, ranging from 6 to 60 ​ml/h. Spinnable aqueous Al–Si solution systems, employing various aluminum sources, were systematically investigated. The optimization of the solution blow spinning apparatus involved the incorporation of a hot air blow device capable of dispensing streams of hot, dry air. Comprehensive investigations were conducted to examine the impact of variables such as spinning solution viscosity, spinning rate, and spinning distance on the resulting mullite fiber diameter and morphology. Following sintering at 1200 ​°C, mullite fiber cotton was successfully synthesized, exhibiting diameters spanning from 500 ​nm to 5 ​μm. These mullite nanofiber cotton demonstrated exceptional attributes, including robust temperature stability (up to 1300 ​°C), remarkable thermal insulation properties and superior filtration efficiency.