Status and strategies for fabricating flexible oxide ceramic micro-nanofiber materials

Oxide ceramic microfibers with low thermal conductivity, high temperature, and corrosion resistance have been widely used in the field of thermal insulation. When the fiber diameter is reduced to the nanoscale (<1000 nm), the high specific surface area and porosity brought by the diameter refinement endow these nanofibers with unique thermal, optical, electrical and other properties, which are expected to be applied in advanced high-tech fields. Oxide ceramic micro-nanofibers (MNFs) belong to a new structural ceramic system, but they suffer from intrinsic hardness and brittleness. We have been committed to developing new textile technologies and fabricating flexible oxide ceramic MNFs. In this review, the development status of oxide ceramic MNFs and their applications are first briefly summarized. Then, the definition of flexibility and flexibility mechanisms of MNFs, as well as the strategies and methods for fabricating flexible oxide ceramic MNFs are comprehensively discussed. Finally, our perspective on the future development of oxide ceramic MNFs is proposed. We suppose that they will develop toward the direction of flexibility, porosity, multifunctionality, thin film, and aerogels, and their functional applications will permeate from the traditional heat insulation to the emerging fields such as flexible electronics and batteries, intelligent artificial muscle, and industrial catalysis.