Sustainable Electrosynthesis of Porous CuN3 Films for Functional Energetic Chips

A porous CuN3 film has been facilely synthesized by a sustainable electroassisted azidation methodology using the template of porous Cu as a precursor. Such porous CuN3 films show excellent performances of both superior energy release and tremendous brisance, which can be tuned by changes of the current density and azidation time. Energy release reaches a maximum of 1200 J·g–1 at a current density of 3.0 mA·cm–2 with a reaction time of 450 s. Meanwhile, the conversion ratio of Cu can reach ca. 31% with ca. 43 wt % of CuN3 in the prepared CuN3 film. In addition, the growth mechanism of the CuN3 film is justified by not only experimental observations but also density functional theory calculations. Compared with the common gas–solid azidation method, this electrosynthesis strategy can lead to great reduction in the reaction time (from >12 h to <10 min) even without the use of dangerous HN3 gas. Moreover, the preparation method here is fully compatible with microelectromechanical system (MEMS) technology, which is of great significance in promising applications for functional energetic chips.