Evolution of Oxidizing Inorganic Metal Salts：Ultrafast Laser Initiation Materials Based on Energetic Cationic Coordination Polymers

摘要： An effective and novel design strategy for ultrafast laser initiating materials has been established on the basis of coordination chemistry for the first time in the present work. In view of the positive effect of Ag ion and perchlorate on laser sensitivity, silver perchlorate as a representative of oxidizing inorganic metal salts was used to construct energetic cationic coordination polymer (ECCPs), which solved the embarrassing situation that these salts are difficult to be directly applied in energetic materials because of unavoidable hygroscopicity and physical mixtures inhomogeneity of oxidant and reductant. With non-energetic nitrogen-rich ligand 3-amino-1H-1,2,4-triazole-5-carbohydrazide (ATCA), one new laser-sensitive Ag(I) based ECCP [Ag(ATCA)ClO4]n (1) was successfully synthesized with compact helical structure proved by X-ray single diffraction crystal data. The physicochemical property evaluation revealed that this Ag-ECCP not only completely discarded the undesirable properties of the silver perchlorate and emerged excellent tolerance to moisture and non-corrosive property to metal shells, but also were endowed with good thermal stability and excellent safety for mechanical stimulation. Moreover, theoretical calculations based on standard molar enthalpy of formation and lead plate explosive test as the actual damage experiment have proved that the compound has a superior detonation performance (up to 6800 m s-1 and 0.511 kcal g-1) than the traditional primary explosives. More importantly, the laser initiation experiment based femtosecond laser testing system and high-speed photography demonstrated that this ECCP was an energetic material with great potential for application of the safety detonator as an ultrafast photosensitive initiating materials for laser direct initiation, whose initiation delay time is as low as 73 ms using only 200 mJ initiation energy.