Developing ceramic nanofibrous membranes for the thermal insulation layer of firefighting protective clothing is vital. However, previous ceramic nanofibrous membranes were brittle and easy to break during service in high-temperature environments. The lack of elastic and compressible properties has limited the high-end applications of ceramic nanofibrous membranes. In this work, elastic and compressible Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes were fabricated via sol–gel electrospinning and calcination in air at different temperatures. The as-fabricated Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes can maintain excellent elasticity and compressibility in the temperature ranging from −196 to 1400 °C. Moreover, they have low thermal conductivity and high working temperatures. These favorable characteristics make the Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes a promising candidate for the thermal insulation layer of firefighting protective clothing.
Lin Wang,Chenfei Gao,Yuhang Jiang,Zepeng Xu,Han Wei,Kangkang Yuan,Xiaotong Jin
Structural evolution is essential for the fundamental understanding of high-temperature behavior and optimizing of ceramic micro/nanofibers. In the present work, the effects of structural evolution on the high temperature stability and flexibility of Al 2 O 3 -ZrO 2 -La 2 O 3 (AZLO) fibrous membranes were fully investigated. The evolution of precursor fiber pyrolysis, phase transformation and microstructure were characterized by TG/DSC, IR, XRD, SEM, ESB and HRTEM. From 800 to 1200°C, the dual-phasic structure of amorphous Al 2 O 3 and fine ZrO 2 and La 2 Zr 2 O 7 grain contributed to the thermal stability and flexibility of AZLO fibrous membranes. At 1300°C, solid-state metathesis reaction between amorphous Al 2 O 3 and intermediate phase La 2 Zr 2 O 7 led to the formation of fine LaAl 11 O 18 and ZrO 2 grain. The interlaced distribution of fine ZrO 2 particles and platelet-like LaAl 11 O 18 became the new fundament of thermal stability and flexibility of AZLO fibrous membranes. AZLO fibrous membranes could maintain its excellent high temperature stability and flexibility up to 1300°C and possessed a low room temperature thermal conductivity of 35.7 mW m −1 K −1 . The present work provided a novel perspective for the rational design of Al 2 O 3 -ZrO 2 fibers from the view of structural evolution.
危险品化学品经营许可证（带存储）