A schematic presentation of the chemical conjugation between the acyl groups on the functionalized nano-onions and the amine groups on the functionalized MoS2 nanosheets. KMnO4, potassium permanganate; H2SO4, sulfuric acid; SOCl2, thionyl chloride; NO, nano-onion; ss, single-strand; COCl, acyl chloride; NH2, amine; SH, thiol