Core-shell particle of aluminum-copper perfluorooctanoate configurations and its ignition and combustion properties

Abstract

Improvements of the ignition and combustion performance of aluminum powder are very beneficial to enhance the combustion efficiency of aluminum powder. In this study, copper perfluorooctanoate (Cu(PFO)2) is firstly synthesized by hydrothermal method, and is used to coat micron-Al by solvent evaporation method. The structure and microscopic morphology of Cu(PFO)2 and the micron-Al coated with Cu(PFO)2 (named as core- shell micro-Al@Cu(PFO)2 configurations) are characterized. The hydrothermal method can obtain Cu(PFO)2 with a high purity of about 98%, and the prepared micro-Al@Cu(PFO)2 configurations have a good core-shell structure. TG-DSC results show that a pre-reaction of aluminum and coating layer Cu(PFO)2 occurs at about 317 °C, and the oxidation degree of the Al particle in micro-Al@15%- Cu(PFO)2 composite particles is 2.2 times that of the pure Al particles. Compared with pure micron Al powder, the ignition and combustion performances of micro-Al@Cu(PFO)2 are significantly enhanced due to the intimate contact and the pre-reaction of micro-Al and Cu(PFO)2. The ignition temperature of micro-Al decreases by at least 249 °C when the coating layer content exceeds 10 wt%. Combustion results show that the higher the content of Cu(PFO)2, the faster the combustion rate of aluminum and the higher combustion efficiency of aluminum. In addition, the good coating effect of Cu(PFO)2 on the surface of Al particles endows micro-Al@15%- Cu(PFO)2 better electrical ignition properties than that of 15%-PTFE/micro-Al. The mechanism studies show that the pre-reaction of Al and coating layer Cu(PFO)2 can corrode the alumina shell of Al particles, and promote the internal aluminum to participate in the oxidization reaction.