In collaboration with Milo Shaffer (Materials, Imperial College London), we investigate the preparation and uses of metal (Cu) and metal oxide (ZnO) nanoparticles. The nanoparticles are prepared from well-defined organometallic reagents, using low-temperature conditions and are produced as colloidal solutions/inks, in common organic solvents. By controlling the hydrolysis of organo-zinc reagents, a useful method to prepare small (3-4 nm), highly crystalline ZnO nanoparticles was developed. Well-dispersed nanoparticles as colloids are produced by carrying out the hydrolysis in the presence of sub-stoichiometric quantities of zinc carboxylate or phosphinate complexes. As part of an on-going investigation into how molecular compounds are transformed into metal oxide nanoparticles, we have recently discovered the structures of a series of zinc cluster complexes relevant to formation of zinc oxide. In particular, by using phosphinate ligands it has been possible to use 31P NMR spectroscopy, in combination with single crystal X-ray diffraction experiments, to identify clusters comprising 4, 6, 9, 11 zinc centres. The low-pressure hydrogenation/oxidation of organo-copper reagents allows the preparation of narrow dispersity, small Cu or Cu2O colloidal nanoparticles which are well-dispersed in common organic solvents.