Directed bonding colloidal assemblies
•The
ability to design and assemble three-dimensional structures from colloidal
particles, such as open structures for photonic band gap applications, is
limited by the absence of specific directional bonds.
•We
introduce a general method for creating the colloidal analogues of atoms with
valence: colloidal particles with chemically functionalized patches that can
form highly directional bonds. These “colloidal atoms” possess all the common
symmetries—and some uncommon ones—characteristic of hybridized atomic orbitals,
includingsp, sp2, sp3, sp3d, sp3d2, and sp3d3.
•The
chemical functionality of the patches is programmable and specific using DNA
with single-stranded sticky ends, thereby creating colloidal atoms from which
different kinds of “colloidal molecules” can be assembled in a straight forward
fashion.
•We
were able to fabricate a vast collection of colloidal molecules and
macromolecules using basic self-assembly methodologies.
The cover illustrates a tetrahedron type
colloidal molecule composed of particles with one or four functionalized
patches
