Electrochemiluminescent Sensor Based On CdTe Quantum Dots

This paper sutdied the eletrochemiluminescent resonance energy transfer betweenluminol, CdTe quantum dots (QDs) and oxygen. The process take place betweenluminol and CdTe QDs could be further enhanced by oxygen. Thus, it provided anexcellent basis for selective and sensitive detection methodology for trace oxygen, aswell as for the formation of singlet oxygen.The first part studied the eletrochemiluminescent resonance energy transfermechanism and the rule of oxygen. The luminol were absorbed onto the surface of QDs.They arrived to the electrode surface with enriched abundance by QDs as the carrier.Because of the property as a semiconductor, the QDs accelerated the oxidation andexcitation of luminol due to the electrolytically yielded holes (h+) when the luminol wasoxidized during the cyclic sweep. The close contact between luminol and QDs madeenergy transfer possible to excite the luminescence of QDs. As once been reported thatCdTe QDs was known to cause the photocatalysis in aqueous solution, the process mayinvolve a transformation of O2to1O2, which efficiently intensifies the ECL. Ourresearch shows a higher sensitivity to oxygen.The second part studied the fabrication of luminol electrochemiluminescent sensorbase on CdTe QDs. Through mixing CHIT and CdTe quantum dots at certain ratio andcasting the composite solution on ITO electrode, we discussed the ECL of CdTe QDsmodified electrode. The research laid the foundation for the preparation of wellperformance of CdTe modified electrode electrochemiluminescence sensor.