Assembly of Ligand-Stripped Nanocrystals into Precisely Controlled Mesoporous Architectures

The properties of mesoporous materials hinge on control of their composition, pore dimensions, wall thickness, and the size and shape of the crystallite building units. We create ordered mesoporous materials in which all of these parameter; are independently controlled. Different sizes (from 4.5 to 8 nm) and shapes (spheres and rods) of ligand-stripped nanocrystals are assembled using the same structure-directing block copolymers, which contain a tethering domain designed to adsorb to their naked surfaces. Material compositions range from metal oxides (Sn-doped In2O3 or ITO, CeO2, TiO2) to metal fluorides (Yb,Er-doped NaYF4) and metals (FePt). The incorporation of new types of nanocrystals into mesoporous architectures can lead to enhanced performance. For example, TiO2 nanorod-based materials withstand >1000 electrochemical cycles without significant degradation.