title: Designing PbSe nanowires and nanorings through oriented attachment of nanoparticles.
abstract: Single-crystal PbSe nanowires are synthesized in solution through oriented attachment of nanocrystal building blocks. Reaction temperatures of 190-250 degrees C and multicomponent surfactant mixtures result in a nearly defect-free crystal lattice and high uniformity of nanowire diameter along the entire length. The wires' dimensions are tuned by tailoring reaction conditions in a range from approximately 4 to approximately 20 nm in diameter with wire lengths up to approximately 30 microm. PbSe nanocrystals bind to each other on either {100}, {110}, or {111} faces, depending on the surfactant molecules present in the reaction solution. While PbSe nanocrystals have the centrosymmetric rocksalt lattice, they can lack central symmetry due to a noncentrosymmetric arrangement of Pb- and Se-terminated {111} facets and possess dipole driving one-dimensional oriented attachment of nanocrystals to form nanowires. In addition to straight nanowires, zigzag, helical, branched, and tapered nanowires as well as single-crystal nanorings can be controllably prepared in one-pot reactions by careful adjustment of the reaction conditions.
authors.affiliation: Nanoscale Materials and Devices Group, IBM T. J. Watson Research Center, Yorktown Heights, NY 10598, USA.
authors.forename: Kyung-Sang
authors.initials: KS
authors.lastname: Cho
authors.forename: Dmitri V
authors.initials: DV
authors.lastname: Talapin
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gaschler
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Murray