Electrogenerated Chemiluminescence of ZnO/MoS2 Nanocomposite and Its Application for Cysteine Detection

ZnO/MoS2 nanocomposite was synthesized by hydrothermal method, and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy, respectively. The morphology of ZnO nanoparticles changed from rod-like to cubic shape when they were deposited onto MoS2 nanosheets, revealing that the MoS2 layer could limit the growth of ZnO. Electrogenerated chemiluminescence (ECL) of ZnO/MoS2 nanocomposite was investigated in neutral condition with S2O82− as coreactant, and strong cathodic ECL signal was obtained, which is stronger than that of pure ZnO nanomaterials. Cysteine exhibited apparent inhibiting effect on ECL signal, and could be sensitively detected. In the range of 1.0 × 10−8 to 1.0 × 10−6 mol L−1, the decreased ECL intensities linearly varied with the logarithm of cysteine concentration, and the detection limit was calculated as 6.5 × 10−9 mol L−1 (3σ). The proposed ECL sensor exhibited high sensitivity and good stability, which revealed the potential application of 2D nanocomposite in ECL sensing field.