An energetic nanocomposite includes fuel nanoparticles and oxidizer nanoparticles covalently bonded to negatively charged functionalized graphene sheets. A preferred example includes Al fuel nanoparticles and Bi2O3 nanoparticles. A preferred method of formation mixes a solution of positively charged fuel nanoparticles, positively charged oxidizer nanoparticles, and negatively charged functionalized graphene sheets having functional groups to bond with the positively charged fuel nanoparticles and positively charged oxidizer nanoparticles. Self-assembly of the energetic nanocomposite is permitted over a predetermined time via the attraction and aggregation of the positively charged fuel nanoparticles positively charged oxidizer nanoparticles and negatively charged functionalized graphene sheets. Additional methods and nanocomposites include unfunctionalized graphene sheets, which can be commercial grade sheets.