Yuan Chen,Yanchen Sun,Gaojie Fang,Wenyao Huang,Quan Wang
The performance of energetic hydrogels—a promising class of water-resistant explosives—is often related to the internal microstructure and chemical reactivity. This study introduces a modification strategy employing copper (II) nitrate trihydrate (Cu(NO 3 ) 2 ·3H 2 O) to simultaneously tailor the hydrogel’s microstructure and enhance its chemical reactivity. The additive functions dually: by acidifying the system, it accelerates cross-linking kinetics and refines sensitized microbubbles; concurrently, it lowers the thermal decomposition barrier of the gel matrix. At an optimal content of 0.75 wt%, the proportion of effective microbubbles (diameter ≤ 100 µm) is maximized to 42.2 %, establishing a dense hotspot network. This microstructural and chemical optimization synergistically boosts detonation performance, increasing velocity by 15.34 % to 4610 m·s⁻¹ and reducing the minimum initiation charge from 50 g to 30 g. Thermal analysis confirms a reduced apparent activation energy and reveals a possible low-temperature exothermic pathway, providing direct evidence for the enhanced reactivity. Crucially, this enhancement does not compromise handling safety, as the initial decomposition temperature remains above 244 °C for all formulations. This work establishes additive-mediated modification as an effective route to engineer energetic materials by concurrently optimizing the microstructure and accelerating the reaction kinetics.
A simple and efficient method was developed to prepare a copper–carbon (Cu–C) catalyst with high oxygen reduction reaction (ORR) activity via direct pyrolysis of a mixture of metal salts (Cu(NO3)2·3H2O and Zn(CH3COO)2) and 1,3,5-benzenetricarbocylic acid at 1010 °C under a N2 stream. It is found that the Cu–C catalyst exhibits superior catalytic activity toward ORR with a half-wave potential of 0.81 V and a four-electron transfer pathway in 0.1 M KOH electrolyte. Generally, it is known that N plays an important role for the high ORR catalytic activities of nonprecious metal-doped carbon materials. Herein, we demonstrate that N is not required for the superior catalytic activity of Cu–C materials. Both the Cu particles and the embedded Cu atoms in the carbon substrate are suggested to provide the ORR active sites. In addition, despite the fact that the Zn is removed during the pyrolysis, the adding of Zn salt in the precursor is important for the enhanced catalytic activity. The evaporation of Zn during the pyrolysis results in the large surface area of the catalyst, which is beneficial to the mass transfer during the catalytic process. Moreover, a large number of carbon defects can be created via the removal of Zn atoms that facilitated the ORR.
危险品化学品经营许可证（带存储）