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Known applications of high energy density materials are impressively vast. Despite this, we argue that energetic materials are still underutilized for common energy purposes due to our inability to control...

Explosive phenomena includes a stunningly wide range of diverse manifestations, such as supernova remnant shocks and solar flares, violent decomposition chemistry and synthesis of superior materials under extreme conditions, weapons, missiles, and high velocity impact damage, fuels for space rocket engines, festive fireworks, and applications of detonation waves in construction industry and microshocks in medicine. With the earliest stages of explosives chemistry in energetic materials remaining poorly understood and constantly posing new science questions, an achievement of a controllable initiation of detonation process represents a particular challenge. Precise tuning of sensitivity to initiation of detonation via photoexcitation appears unreachable because all known secondary explosives are wide band gap insulators. This research demonstrates how YAG:Nd laser irradiation triggers explosive decomposition of PQ−PETN composites formed by pentaerythritol tetranitrate (PETN), high energy density material, mixed with photosensitive 9,10phenanthrenequinone (PQ). We suggest, explore, and validate a feasible mechanism of photocatalytic decomposition of explosives activated by the laser excitation with the energy of 1.17−2.3 eV and the wavelength of 1064−532 nm.

The development of methods ensuring reliable control over explosive chemical reactions is a critical task for the safe and efficient application of energetic materials. Triggering the explosion by laser radiation is one of the promising methods. In this work, we demonstrate a technique of applying the common industrial high explosive pentaerythritol tetranitrate (PETN) as a photosensitive energetic material by adding zinc oxide nanopowders doped with copper and iron. Nanopowders of ZnO:Fe and ZnO:Cu able to absorb visible light were synthesized. The addition of one mass percent nanopowders in PETN decreased the threshold energy density of its initiation through Nd:YAG laser second harmonic (2.33 eV) by more than five times. The obtained energetic composites can be reliably initiated by a CW blue laser diode with a wavelength of 450 nm and power of 21 W. The low threshold initiation energy and short irradiation exposure of the PETN-ZnO:Cu composite makes it applicable in laser initiation devices. PETN-ZnO:Cu also can be initiated by an infrared laser diode with a wavelength of 808 nm. The proposed photochemical mechanism of the laser-induced triggering of the explosion reaction in the studied energetic composites was formulated. The results demonstrate the high promise of using nanomaterials based on zinc oxide as a sensitizer of industrial energetic materials to visible laser radiation.