Exfoliation of self-assembled 2D aluminum synthesized via magnetron sputtering

•Large 2D aluminum particles were synthesized via magnetron sputtering.•The formation of layers is suggested with stress and is simulated via finite analysis.•Sonication and annealing were utilized to exfoliate the 2D aluminum. Two-dimensional materials have been rapidly developed in recent years. As a type of two-dimensional material, 2D metals exhibit many unique physical and chemical properties. Here, we prepared two-dimensional aluminum materials via magnetron sputtering. The layers were exfoliated via sonication and annealing methods (thermal exfoliation methods). After exfoliation, the layers were observed via optical microscopy, scanning electron microscopy and transmission electron microscopy. The atomic force microscopy results show that the thicknesses of the layers range from ∼1 nm to ∼45 nm. The simulation results supported those two-dimensional layers formed in a self-assembly process.