Template synthesis and characterization of chiral organic nanotubes and nanowires

Optical materials based on molecular nanoparticles

A major part of contemporary nanomaterials research is focused on metal and semiconductor nanoparticles, constituted of extended lattices of atoms or ions. Molecular nanoparticles assembled from small molecules through non-covalent interactions are relatively less explored but equally fascinating materials. Their unique and versatile characteristics have attracted considerable attention in recent years, establishing their identity and status as a novel class of nanomaterials. Optical characteristics of molecular nanoparticles capture the essence of their nanoscale features and form the basis of a variety of applications. This review describes the advances made in the field of fabrication of molecular nanoparticles, the wide spectrum of their optical and nonlinear optical characteristics and explorations of the potential applications that exploit their unique optical attributes.

Porous one-dimensional nanostructures through confined cooperative self-assembly

We report a simple confined self-assembly process to synthesize nanoporous one-dimensional photoactive nanostructures. Through surfactant-assisted cooperative interactions (e.g., π-π stacking, ligand coordination, and so forth) of the macrocyclic building block, zinc meso-tetra (4-pyridyl) porphyrin (ZnTPyP), self-assembled ZnTPyP nanowires and nanorods with controlled diameters and aspect ratios are prepared. Electron microscopy characterization in combination with X-ray diffraction and gas sorption experiments indicate that these materials exhibit stable single-crystalline and high surface area nanoporous frameworks with well-defined external morphology. Optical characterizations using UV-vis spectroscopy and fluorescence imaging and spectroscopy show enhanced collective optical properties over the individual chromophores (ZnTPyP), favorable for exciton formation and transport.

General method for the synthesis of crystalline organic nanorods using porous alumina templates

Nanorods composed of a variety of conjugated organic molecules were synthesized using an anodized alumina template and solvent annealing; detailed study of 200 nm thick 2,7-di-t-butylpyrene rods showed they are crystalline, with single domains extending over several microns.