(Centro de Nanotecnología Aplicada, Facultad de Ciencias Universidad Mayor, Santiago, Chile )
Topic: New burning rate catalysts of composite solid propellants based on graphene and metal nanoparticles.
One of the critical aspects of the outer-space race is the development of safe, stable, and efficient fuels. Composite solid propellants (CSP) appear as an option; however, their energy release is still low to reach faraway destinations with only one charge. The decomposition properties of ammonium perchlorate (AP), the primary oxidizer of a rocket motor, can be tuned by adding a burn rate catalyst, which can alter its highest decomposition temperature, and therefore increase the combustion rate. Traditionally, ferrocene derivatives and fine-grained metal oxides have been used as burning rate catalysts. The effect of metallic micro- and nanoparticles (NP) on the decomposition of AP has been widely assessed. By now, it is well known that a higher surface means better catalytic effect, and thus NP of transition metals have resulted as better catalysts than microparticles. Nonetheless, most of the production procedures of transition metal nanoparticles require calcination as a final step, which is an energy-consuming process, requires specialized equipment, and has a direct impact on the final price of the catalyst. In addition, NPs aggregate easily without the presence of a proper protective agent.
In this work, cobalt and copper nanoparticles were effectively stabilized by reduced graphene oxide (rGO) without extremely high temperatures or calcination steps. The agglomeration was controlled by the support of reduced graphene oxide (rGO) layers. The effect of the new catalysts on the decomposition of AP was compared to metallic nanoparticles. Both catalysts diminished the high decomposition temperature of AP significantly, but in the case of the catalysts with rGO, the energy release increased even more.
M.B. Camarada is an Associate Professor in the Science Faculty at Universidad Mayor, Santiago, Chile. She is also the Director of the Center for Applied Nanotechnology (CNAP) at the same institution (https://cnap.umayor.cl/) since 2017, where she has established externally funded research programs, mentored undergraduates, PhD students, and postdocs. CNAP has 9 PI’s and financial support from Chile, USA, and China. During her career, she has co-authored more than 35 peer-reviewed publications and has received funding as a PI and co-PI on grants from the Chilean Science Foundation (Fondecyt 1180023 and 1161297), the US Army (RDECOM W911NF1810398) and the National Foundation of Science of China (NSFC 51962007). Her research is focused on the development of new nanomaterials with application on electrochemical sensor platforms and catalysts for the decomposition of composite solid propellants.