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A new nitrogen-rich energetic material, hydrazinium 3,5-dinitroamino-1,2,4-triazole (HDNAT), was synthesized. Thermal behavior and non-isothermal decomposition kinetics of HDNAT were studied with DSC and TG/DTG methods. The non-isothermal decomposition kinetic equation is $$\frac{{{\text{d}}\alpha }}{{{\text{d}}T}} = \frac{{10^{19.37} }}{\beta }6(1 - \alpha )^{{{2 \mathord{\left/ {\vphantom {2 3}} \right. \kern-0pt} 3}}} [1 - (1 - \alpha )^{{{1 \mathord{\left/ {\vphantom {1 3}} \right. \kern-0pt} 3}}} ]^{{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-0pt} 2}}} \exp ( - 188.6 \times 10^{3} /RT)$$ . Self-accelerating decomposition temperature and critical temperature of thermal explosion of HDNAT are 168.1 and 178.1 °C, respectively. Specific heat capacity of HDNAT was determined with a micro-DSC method and the molar heat capacity is 258.96 J mol K at 298.15 K. Adiabatic time-to-explosion of HDNAT is about 100 s. The impact sensitivity, friction sensitivity, detonation velocity and detonation pressure of HDNAT are >13.1 J, 84 %, 9.0 km s and 36.0 GPa, respectively. [ABSTRACT FROM AUTHOR]

An efficient approach for the synthesis of fullerene(C60)-bis(2,4,6-trinitrophenethyl) malonate (FTNPEM) has been achieved via the Bingel reaction of bis(2,4,6-trinitrophenethyl) malonate (TNPEM) C60 with a yield of 37% (based on consumed C60). A 2,4,6-trinitrophenyl ethanol (TNPE) was prepared by the reaction of TNT and formaldehyde under the weak base condition. The bis(2,4,6-trinitrophenethyl) malonate (TNPEM) was obtained via the esterification reaction of malonyl dichloride and TNPE with a yield of 65%. In addition, the products were characterized by UV-Vis, ¹H-NMR, FT-IR, 13C-NMR, MS and elemental analysis. TG-A was employed to evaluate the thermal stability of the FTNPEM at heating of rates 20 °C/min in air. Moreover, as a new energetic fullerene derivative, energetic properties of FTNPEM by using density functional theory (DFT) method were calculated by designing isodesmic reactions. The theoretical detonation velocity is 4.530 km/s, and the theoretical detonation pressure is 9.034GPa. [ABSTRACT FROM AUTHOR]

Three high-energy salts ( 3 , 4 and 5 ) based on oxy-bridged bis( gem -dinitro) furazan with potassium and nitrogen-rich cations were reported. Their structures were fully characterized and confirmed by NMR ( 1 H, 13 C), IR spectroscopy, elemental analysis and single crystal X-ray diffraction. The thermal decomposition behaviors were studied by DSC and TG methods. And, the decomposition process of 5 was studied by the thermolysis in-situ rapid-scan FTIR. The non-isothermal kinetics parameters were obtained by Kissinger’s and Ozawa’s methods, respectively. The activation entropy (Δ S ≠ ), activation enthalpy (Δ H ≠ ), activation Gibbs free energy (Δ G ≠ ) and the critical temperature of thermal explosion were calculated. [ABSTRACT FROM AUTHOR]

A new cadmium complex of 1,1-diamino-2,2-dinitroethylene (FOX-7) was synthesized and structurally determined. Central Cd2+is coordinated by six nitrogens from four NH3molecules and two FOX-7?anions to form an octahedral structure. The thermal decomposition of Cd(NH3)4(FOX-7)2was studied with differential scanning calorimeter and TG–DTG methods. The apparent activation energy and pre-exponential constant of the exothermic process are 220.6 kJ M?1and 1017.86s?1, respectively. Cd(NH3)4(FOX-7)2is sensitive. [ABSTRACT FROM AUTHOR]

We present a systematic study of a mild approach for the activation of metal oxides, involving reactivity and self-assembly in the solid state, which enables their solvent-free chemical separation and direct solvent-free and low-energy conversion into coordination polymers and open metal-organic frameworks (MOFs). The approach is inspired by geological biomineralization processes known as mineral weathering, in which long-term exposure of oxide or sulfide minerals to molecules of biological origin leads to their conversion into simple coordination polymers. This proof-of-principle study shows how mineral neogenesis can be mimicked in the laboratory to provide coordination polymers directly from metal oxides without a significant input of either thermal or mechanical energy, or solvents. We show that such "aging" is accelerated by increased humidity, a mild temperature increase and/or brief mechanical activation, enabling the transformation of a variety of high-melting (800 °C-2800 °C) transition (MnII, CoII, NiII, CuII, and Zn) and main group (Mg and PbII) oxides at or near room temperature. Accelerated aging reactions are readily scaled to at least 10 grams and can be templated for the synthesis of two-dimensional and three-dimensional anionic frameworks of Zn, Ni(II) and Co(II). Finally, we demonstrate how this biomineralization- inspired approach provides an unprecedented opportunity for solvent-free chemical segregation of base metals, such as Cu, Zn and Pb, in their oxide form under mild conditions. [ABSTRACT FROM AUTHOR]

A new energetic zinc-FOX-7 complex (FOX-7 = 1,1-diamino-2,2-dinitroethylene), Zn(NH3)2(FOX-7)2, was synthesized and structurally characterized by single crystal X-ray diffraction. Zn2+was coordinated by four nitrogens from two ammonias and two FOX-7?anions, forming a distorted tetrahedron. Thermal decomposition of Zn(NH3)2(FOX-7)2was studied by differential scanning calorimetry and thermogravimetry/differential thermogravimetry. The apparent activation energy and pre-exponential constant of the first decomposition process are 144.8 kJ M?1and 1013.99?s?1, respectively. The self-accelerating decomposition temperature and critical temperature of thermal explosion of Zn(NH3)2(FOX-7)2are 183.2 and 195.8?°C, respectively. The thermal stability of Zn(NH3)2(FOX-7)2is good, but Zn(NH3)2(FOX-7)2is still sensitive. [ABSTRACT FROM PUBLISHER]

The layered titanate H 1.07 Ti 1.73 O 4 ·nH 2 O (HTO) is a useful and unique precursor for the facile preparation of Ag@AgCl/HTO composite with enhanced visible light photoactivity. The Ag@AgCl within Ag@AgCl/HTO composite is evenly distributed on the HTO surface, and the Ag/Ti ratio can be easily controlled by ion exchange reaction. The photocatalytic experiment results show that the Ag@AgCl/HTO photocatalyst with Ag/Ti ratio of 0.13 has the highest photoactivity for the RhB degradation under visible light irradiating. The transient photocurrent responses, electrochemical impedance spectroscopy, and photoluminescence spectrum of samples are studied, indicating the introduction of Ag@AgCl into HTO surface can promote the separation efficiency of the photoinduced electron-hole pairs. Moreover, by means of the trapping experiment of active species, it can be concluded that h + and O 2 − are the main active species during the visible light photocatalytic reaction. The photocatalytic mechanism is also discussed. [ABSTRACT FROM AUTHOR]

The synthesis and crystal structure of oxy-bridged bis(1 H -tetrazol-5-yl)furazan ( 2 ) were reported. The thermal behavior of 2 was investigated by DSC and TG–FTIR–MS coupling technique. The results showed that the thermolysis of 2 included two stages. The rupture of tetrazole ring occurred with the release of N 2 in the first stage. In the second stage, the striping of HCN from schiff base radical followed by the fragmentation of furazan ether moiety, which leading to the formation of N 2 O, NO and polymer. Furthermore, two decomposition pathways of 2 under electron impact condition were proposed, and the fracture of tetrazole ring and ether bond were considered as the initial step of molecule decomposition, respectively. [ABSTRACT FROM AUTHOR]