Electrochemiluminescence Enhancement of CdTe Quantum Dots by the Addition of Silver(I) Ions

Abstract Water-soluble CdTe quantum dots (QDs) were synthesized by using a 3-mercaptopropionic acid (MPA) capped method. Stable electrochemiluminescence (ECL) was obtained when the CdTe QDs were immobilized onto a glassy carbon electrode (GCE) by Layer-By-Layer (LBL) assembly of CdTe QDs and polydiallyldimethylam-monium chloride (PDDA) by using 2-(dibutylamino)-ethanol (DBAE) as a co-reactant. The ECL enhancement of CdTe QDs by the addition of silver(I) ions was also investigated. The maximum enhancement factor about 4 was obtained on a GCE in the presence and absence of the co-reactant. The enhancement was observed in phosphate-citric acid and phosphate buffer solutions (PBS), but not in borate buffer solution (BBS). This was newly formed Ag nanoparticles or silver(I) complex with large surface area and high catalytic activity in the phosphate-citric acid and phosphate buffer solutions, thus resulting in ECL enhancement. Keywords: Ag+ ElectrochemiluminescenceLayer-by-layerQDs This work was supported by the National Natural Science Foundation of China (No. 90713022), the National Key Basic Research Development Project of China (No. 2007CB714500), and the Project of Chinese Academy of Sciences (No. KJCX2. YW. H09 and KJCX2. YW. H11).