Fabrication of continuous ZrB2 nanofibers derived from boron-containing polymeric precursors

Continuous ceramic nanofibers of ZrB 2 were synthesized via electrospinning combining with polymeric precursor method. The electrospinning solution was prepared from the reaction of Polyzirconoxane (PZO) with 2-Hydroxybenzyl alcohol and boric acid followed by the addition of polyvinylpyrrolidone (PVP). The influences of the solution properties and B/Zr molar ratio on electrospinning were investigated. The electrospun precursors and heat-treated nanofibers were characterized by XRD , SEM, EDS , TEM and Raman. The results showed that pyrolysis at 350 °C helped to stabilize the fibers morphology and ZrB 2 nanofibers were obtained by pyrolyzing the precursor fibers at 1400 °C for 2 h in argon. ZrB 2 nanofibers maintained the excellent fibrous morphology in all the samples. ZrB 2 nanofibers are composed of uniformly nanosized ZrB 2 particles. The average crystallite size of ZrB 2 particles using Scherrer equation is 25 nm. The atomic percentages of zirconium and boron in the product formed in argon at 1400 °C were 17.06% and 33.73% respectively, which is very close to the stoichiometric ZrB 2 .