Strategies for Achieving Balance between Detonation Performance and Crystal Stability of High-Energy-Density Materials

Abstract

Performance-stability contradiction of high-energy-density materials (HEDMs) is a long-standing puzzle in the field of chemistry and material science. Bridging the gap that exists between detonation performance of new HEDMs and their stability remains a formidable challenge. Achieving optimal balance between the two contradictory factors is of a significant demand for deep-well oil and gas drilling, space exploration, and other civil and defense applications. Herein, supercomputers and latest quantitative computational strategies were employed and high-throughput quantum calculations were conducted for 67 reported HEDMs. Based on statistical analysis of large amounts of physico-chemical data, in-crystal interspecies interactions were identified to be the one that provokes the performancestability contradiction of HEDMs. To design new HEDMs with both good detonation performance and high stability, the proposed systematic and comprehensive strategies must be satisfied, which could promote the development of crystal engineering of HEDMs to an era of theory-guided rational design of materials. ''materials genome'' approach, based on the theoretical calculations of six-member aromatic and

Applying machine learning to balance performance and stability of high energy density materials

“…Pearson correlation coefficients listed in Table S4 indicate that the presence of gaseous N 2 in the reaction products is also important to detonation properties. These results are consistent with our recent knowledge-driven findings ( Li et al., 2020a , 2020b , 2020c ) that the generation of large amount of CO 2 and N 2 gas is conducive to the improvement of Q max , D , and p C-J of HEDMs. Furthermore, it was found that molecules, with high MW value and energetic rings connected via bridge bonds or with non-planer heterocyclic or cage-like backbones, are responsible for the better Q max of these molecules, whereas they have only a minimal influence on D and p C-J ( Figure S27 ; Supplemental information ).…”

“…Pearson correlation coefficients presented in Table S4 ( Supplemental information ) indicate that the contribution of the presence of gaseous H 2 O in the products is negative for obtaining large value of Q max , and the contribution of the presence of solid C in the products has also negative effect on obtaining large values of D and p C-J . These results are consistent with the recent finding ( Li et al., 2020a , 2020b , 2020c ) that high proportion of H 2 O in the products leads to a lower Q max and high content of solid carbon clusters in the detonation products, which are obtained due to the oxygen deficiency in the structure of an HEDM, leads to a drastic decrease in D and p C-J of HEDMs.…”

“…The crystal level parameters include space group, number of molecules in one primitive cell, packing types, packing coefficient (PC), ρ, ρ N , OB, intermolecular HB count, intermolecular HB strength, intermolecular HB length, and in-crystal mixture with hydrogen-rich molecules or energetic molecules. The molecular level parameters include shape of molecular backbones; molecular weight (MW); intramolecular bond length; intramolecular bond strength; number of critical functional groups, such as –NO 2 , –NH 2 , –OH, –CH 3 , and –N 3 ; as well as the distribution of detonation products, including gaseous CO 2 , H 2 O, N 2 , O 2 , and NH 3 and solid C. Although part of the calculated data for 118 HEDMs was mentioned in our recent studies ( Li et al., 2020a , 2020b , 2020c ), in the present work, the calculated data of physicochemical parameters for these compounds were significantly increased and further DFT calculations for additional 35 HEDMs were performed to enlarge the dataset.…”

“…Both strategies were capable of leading to the increase of the density (ρ) and heat of formation of the energetic molecules, facilitating the promotion of their detonation performance ( Hu et al., 2020 ). However, when the increase in the OB leads to better performance, it pays the price of higher sensitivity and lower stability of the resulting HEDM ( Wang et al., 2018 ; Li et al., 2020a , 2020b , 2020c ). Moreover, the increase of ρ N in various nitrogen-rich HEDMs inevitably introduces N–N bonds, the low bond strength of which would result in reduced stability of such molecules ( Tang et al., 2017 ; Zong et al., 2020 ).…”

“…For example, hydrogen bonding (HB) plays a vital role in optimizing both detonation performance and crystal stability. Crystal structures of HEDMs rich in HBs were shown to have better stability, and expressed enhanced heat resistance and improved insensitivity to impact and shock stimuli , versus compounds with limited HB amount in their crystal structures ( Rupeng et al., 2019 ; Li et al., 2020a , 2020b , 2020c ; Zhang et al., 2019a , 2019b , 2019c , 2019d ). For example, when compared with neutral tetranitroamino HEDMs, corresponding energetic salts showed better thermal and mechanical stabilities, owing to the extensive HB interactions between cations and anions ( Lang et al., 2020 ).…”