Highly Soluble Ligand Stabilized Tin Oxide Nanocrystals: Gel Formation and Thin Film Production

Highly soluble ligand stabilized tin oxide nanocrystals have been prepared by the postsynthetic modification of hydrous tin oxide with the simple short-chain carboxylic acids, acetic acid and trifluoroacetic acid. The surface modified nanoparticles are soluble in common organic solvents at concentrations of up to 2 g/mL and may be stored indefinitely in the solid-state with no loss of solubility. The nature and role of the surface carboxylate groups has been assessed through a combination of thermogravimetric analysis and infrared spectroscopy. The effect of surface modification on the sintering behavior of the nanomaterials has also been investigated. Tuning the surface chemistry of the hybrid nanocrystals allows the generation of monolithic gels, while their high solubility permits the preparation of high quality thin films using simple solution processing techniques.