Synthesis of CdS hierarchical microspheres and their application in electrochemiluminescence sensing

CdS microspheres with hierarchical structures were prepared with sodium dodecylbenzenesulfonate (SDBS) as structure directing reagent. SEM analysis indicated that the CdS microspheres were constructed with CdS nanosheets, which were further built up with assembled CdS nanoparticles. Optical investigation showed that the obtained CdS microspheres have an UV-vis absorption at 445 nm and photoluminescence (PL) emissions at 498 and 573 nm. The CdS hierarchical microspheres were immobilized on a glassy carbon electrode and the electrochemiluminescence (ECL) properties were investigated. The first application to sensing H₂O₂ was studied based on ECL from CdS hierarchical microspheres. A linear relation between the ECL intensity and H₂O₂ concentration, I = 2.4212 + 2.1713 c, was obtained with a detection limit of 1 × 10⁻⁸ mol·L^− 1.