Preferential solvation in aromatic nucleophilic substitution reactions is discussed using a kinetic study complemented with quantum chemical calculations. The model system is the reaction of a series of secondary alicyclic amines toward phenyl 2,4,6-trinitrophenyl ether in aqueous ethanol mixtures of different compositions. From solvent effect studies, it is found that only piperidine is sensitive to solvation effects, a result that may be traced to the polarity of the solvent composition in the ethanol/water mixture, which points to a specific electrophilic solvation in the aqueous phase.

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Graphene oxide quantum dot (GOQD) and reduced GOOD (rGOQD) were synthetized using a simple and straight methodology based on an oxidative treatment and sonication. GOQD and rGOQD were used as supporting agents for the in situ generation of gold nanoparticles, avoiding the use of additional stabilizers. GOQD resulted as a better support than rGOQD because of the presence of higher functional groups that can interact with gold. Theoretical studies through density functional theory revealed the important role of the epoxy groups of GOQD on the stabilization of gold. GOQD and GOQD-Au were tested for the first time as catalysts for the decomposition of solid composite propellants. GOQD not only lowered the decomposition temperature of ammonium perchlorate (AP) but also enhanced the exothermic heat of AP, in comparison to graphene and GO. GOQD-Au increased the energy release; however, the effect on the decrease of the decomposition temperature of AP was not as significant as other previous reported catalysts.

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The synergistic effect of a copper and reduced graphene oxide nanocomposite increased the energy release in the thermal decomposition of ammonium perchlorate.