Applications of the 1,3-dithiole unit in a post-TTF era

✍ Scribed by Dr. Thomas K. Hansen; Prof. Jan Becher

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 454 KB
• Volume: 5
• Category: Article
• ISSN: 0935-9648
• DOI: 10.1002/adma.19930050415

✦ Synopsis

News made? An acidic aqueous S,Oge solution makes the most efficient and stable junction reported so far.['*] Under negative bias, diffusion-limited hole injection from SO?', an electrolyte reduction product, apparently occurs across the capped Si wire surface, yielding light emission with only a relatively minor accompanying corrosion of the porous Si.

This electroluminescence experiment is in some sense the "inverse" of a recently reported nanocrystalline CdSe/solution p h o t o d i ~d e . [ ~~l Photogeneration of an electron-hole pair in a 4 nm CdSe nanocrystal, in a porous crystallite electrode, produces efficient hole transfer to the electrolyte and electron collection by the electrode. The electron moves through many CdSe nanocrystals without recombination with another hole. Holes are thought to immediately transfer to the electrolyte. If this is correct, then efficient charge separation is not due to field-induced transport, as occurs at a normal bulk junction, but to differences in the transfer rate across the nanocrystal/solution interface.

These two encouraging results suggest it might be worthwhile investigating the physics of these unusual junctions in detail.