Tunable Composition of Mixed Self‐Assembled Shell‐by‐Shell Structures on Nanoparticle Surfaces.

The formation of mixed shell‐by‐shell (SbS) systems with tunable shell compositions is demonstrated by using molecular self‐assembly driven by chemical recognition motifs. Aluminum oxide nanoparticles (AlOx‐NPs) act as template surface for a self‐assembled monolayer (SAM) of either partially fluorinated fluoroalkyl or alkyl chained phosphonic acid derivatives or defined stoichiometric mixtures of those. By providing an equimolar mixture of corresponding fluoroalkyl and alkyl‐chained amphiphiles in water, the stoichiometry of underlaying mixed SAM on the NP‐surface preferentially directs the composition of the secondary self‐assembly. The composition of the shell‐by‐shell assemblies is studied by high performance liquid chromatography and fluorescence spectroscopy. The concept allows the formation of NP‐templated vesicle‐like bilayer structures, even consisting of orthogonal chain structures in tunable composition driven by chemical recognition and hydrophobic segregation. [ABSTRACT FROM AUTHOR]