Large area layered ultrathin films of metal-diacid via liquid/liquid interfacial self-assembly

Abstract Large area layered ultrathin films have attracted much attention in recent years, as they have ordered structure, unique properties and potential applications in various areas, such as transportation, separation and catalysis. Herein, we reported the successful preparation of large area layered ultrathin films of a bola-type amphiphilic molecule, perfluorodecanedioic acid (PFDDA) at the liquid/liquid interface in the absence or presence of metal ions. It was found that the ultrathin thin film of PFDDA/Zn(II) has a hexagonal closed packed crystal structure with the crystal parameters of a = 0.302 and c = 1.9 nm. The formation of the film was attributed to the weaker intermolecular interactions, the restriction of the interfacial phase, and the epitaxial growth. However, dodecanedioic acid (DDDA) and docosanedioic acid (DCDA) formed ultrathin nanosheets instead of large area films through this approach, reflecting different self-assembly behavior of the perfluorocarbon chains and the hydrocarbon chains.