Greatly enhanced electrochemiluminescence of CdS nanocrystals upon heating in the presence of ammonia

CdS nanocrystals (NCs) usually exhibit very weak electrochemiluminescence (ECL) emission. It is showed that when CdS NCs were treated by heating in the presence of ammonia (heated-CdS-NH3), greatly enhanced ECL was observed. The ECL of the heated-CdS-NH3 modified glassy carbon electrode (heated-CdS-NH3/GCE) in phosphate buffer solution (pH 7.0) containing 0.1 M K2S2O8 was ca. 310 times higher than that of CdS/GCE. The treatment caused the changes in the morphology and surface electronic structure of CdS NCs, which facilitated the reduction process of CdS, consequently improved the quantity of the excited states (CdS*), leading to enormous enhancement in ECL (c) 2010 Elsevier B.V. All rights reserved.