Facile synthesis of high tightly ordered Al/CuO core-shell nanowire arrays and the effect of surface density on combustion

Abstract The core-shell nanowires structure has increasingly attracted the attention in energetic-material applications due to the high reactive interface. However, the influences for surface density of nanowires on the exothermic capability, ignition response, even reaction process are still rarely reported, which is probability benefit to give more energy release for micron combustion. Here, CuO nanowires are prepared by electrochemical and chemical etching methods, subsequently Al is sputtered on CuO nanowires, and a series of different loading density of Al/CuO nano-thermite are prepared. As results, characterizations show that the CuO nanowires prepared by the electrochemical method has the high surface density and a homogeneous structure, which is beneficial to the contact between Al and CuO. Correspondingly, TG/DSC tests show that the heat release per unit area of nano-thermite prepared by electrochemical-sputtering is 8 times that of the product prepared by chemical-sputtering. Its obvious reduction of activation energy (181.142 kJ/mol) could be attributed to the excellence interaction of thermite components. Moreover, the high surface density structure of nano-thermite is easier to be ignited with lower ignite energy of only 10 mJ. Its significantly increase in combustion rate, flame area or intensity also demonstrated the great advantage in micron igniter or combustion devices.