Quantum dot chemiluminescence

We report the first observation of band gap chemiluminescence of semiconductor quantum dots in solution and in nanoparticulate layers. The spectral position of the band gap chemiluminescence of CdSe/CdS core shell and InP nanocrystals depends on their particle size, allowing thus an efficient tuning of the emission color with superior color purity inherent for monodisperse samples. The efficiency of nanocrystal chemiluminescence can be dramatically enhanced by applying a cathodic potential to the nanoparticulate layers made from CdSe or CdSe/ CdS core - shell nanocrystals. In this case electrochemical n-doping of the particles via electron injection provides a "quantum confined cathodic protection" against nanocrystal oxidative corrosion upon hole injection and allows the achievement of efficient and stable electrogenerated chemiluminescence.