Core-shell structured AP/Fe3O4 composite with enhanced catalytic thermal decomposition property: Fabrication and mechanism study

Abstract

To address the aggregation problem of nanocatalysts in ammonium perchlorate (AP), AP/Fe3O4 core-shell composites (CSC) were synthesized by nanodispersion-assisted antisolvent recrystallization induced self-assembly method. DFT and FTIR test results reveal that covalent bonds between citrate and Fe3O4 along with hydrogen bonds between citrate and AP drive the formation of AP/Fe3O4 CSC. With coating 5.4 wt% Fe3O4, the high-temperature decomposition peak temperature of AP is decreased by 91.3 °C, the heat release is increased by 125% and the apparent activation energy is lowered by 47.9%. AP/Fe3O4 CSC exhibit excellent thermal decomposition performance because the highly dispersed nanocatalysts on AP surface provide more catalytic sites and accelerate the reaction heat transferring from burning surface to condensed AP. Guided by this strategy, AP/Co3O4 and AP/Fe2O3 CSC were also prepared with enhanced thermal decomposition performance, which indicates this strategy has good applicability to improve the catalytic performance of nano metal oxides for AP decomposition.