Preparation and Characterization of Novel Pyrophoric LiFeX Nanopowders

In the past decades, considerable efforts have been made to produce pyrophoric iron substrates for military application. Usually, pyrophoric iron is prepared by thermal reduction of nanoparticles of Fe₂O₃ in hydrogen. However, the pyrophoric iron produced has a very short burning duration (<10sec) when exposed to oxygen or air. In this research, very promising compound LiFe_X was identified as a substitute for nanosize α-Fe. Pyrophoric LiFe_X was prepared by reduction of mesoporous LiFe₅O₈ in hydrogen at temperatures between 300^oC and 600^oC. It was found that synergy between Li and Fe did show better burning characteristics in air than pure α-Fe. Novel LiFe_X pyrophoric substrates were made by dip coating or ultrasonic coating of LiFe₅O₈ on porous alumina, followed by thermal reduction in hydrogen. Details of preparation of LiFe₅O₈ and the formation of LiFe_X will be presented. In addition, burning characteristics of LiFe_X pyrophoric substrate will also be presented.