Recent advances in the preparation of semiconductors as isolated nanometric particles: new routes to quantum dots

Nanoparticles of semiconductor materials have been the subject of intense research in the last five years owing to the novel electronic, catalytical and optical properties observed in such materials. The unusual properties of these so called quantum dots can be attributed to two main factors: the large surface to volume ratio of atoms and the confinement of charge carriers in a 'quantum mechanical box'. Small particles of semiconductors have been prepared by a number of routes, often using colloidal chemistry methods but more recently using organometallic routes. The recent advances have resulted in high quality nanoparticles which have been incorporated into simple devices. In this article we cover some of the key advances in the preparation of nanometric particles of semiconductors. The cover illustration depicts three sizes of TOPO capped CdSe.