Hierarchical synthesis of ordered and oriented complex nanostructures

by Zhang, Tierui; Keeter-Brewer, Mary; Dong, Wenjun; Tian, Z. Ryan

Hierarchical, ordered, and oriented ZnO complex nanostructures have been designed and fabricated via low-temperature and hydrothermal routes through sequential nucleation and growth processes. The results have suggested that the organoamine would preferentially adsorb on the columnar facets of the primary rod structure of ZnO, while the organic acid would prefer to be on the basal facet. Such selective adsorptions have induced heterogeneous nucleation or localized dissolution on different crystal facts, empowering us to design and alternatively grow secondary and tertiary nanostructures. This new approach in nanosynthesis has resulted in a range of rich morphologies (e.g. nano-wheels, nano-urchins, and nano-castles) with unique application potentials in, for instance, catalysis, separation, solar cell, and nanotherapeutics. This work would shed new light on rational design and application-targeted synthesis of functional materials in nanoscale, and help understand the fundamental sciences that govern the interface bonding or interaction(s) between two differently structured nanoscale building blocks.