Combustion characterization and modeling of novel nanoenergetic composites of Co3O4/nAl†
Abstract
Nanoenergetic materials have been widely explored for obtaining rapid release of energy, burn-speeds and high pressurization rates. In this study, we have synthesized Co3O4 nanobelts via a simple solid-state process and further integrated as-prepared Co3O4 and calcined Co3O4 (at 400 °C for 4 hr) (Co3O4-400) with nano-aluminum (nAl) to realize novel bulk nanoenergetic systems of Co3O4/nAl and Co3O4-400/nAl respectively. The heat of reaction and combustion performance of these nanoenergetic systems are studied by thermogravimetric and differential scanning calorimetry (TG-DSC), combustion front-wave speed and pressure–time characteristics measurements. The heat of reaction has been measured to be 0.96 kJ g−1 for Co3O4/nAl and 1.02 kJ g−1 for Co3O4-400/nAl nanoenergetic systems. The Co3O4/nAl nanoenergetic system is able to develop mild peak pressure (12.6 ± 1 to 20 ± 2 MPa) and pressurization rate (0.08 ± 0.05 to 0.14 ± 0.05 MPa μs−1) having a characteristics of low gas generation, which can be harnessed in low intensity pressure-pulse based microporation of soft matters like bacterial cells without any lysis. The calcined Co3O4 oxidizer is capable to develop more reactive nanoenergetic system than Co3O4/nAl, reflecting the generation of moderate peak pressure (26 ± 2 to 32.6 ± 3 MPa) and pressurization rate (0.29 ± 0.1 to 0.47 ± 0.1 MPa μs−1). The propagating flames of (Co3O4/Co3O4-400)/nAl are observed accelerating during instrumented burn tube combustion experiment with front combustion front-wave speed ranging from 480 ± 25 to 830 ± 75 m s−1. Through this paper, the Co3O4 nanoenergetic oxidizers can be utilized in the generation of low to moderate pressure pulses to transport biological materials to soft matters.