ZnO nanoparticles on MoS microflowers for ultrasensitive SERS detection of bisphenol A.

A heterojunction microcomposite was synthesized that consists of ZnO nanoparticles (ZnO NPs) anchored on MoS microflowers (MoS MFs). The material is shown to enable trace level detection of the pollutant bisphenol A (BPA). The microcomposite was characterized by XRD, XPS, SEM and TEM. In addition, coupling reaction between phenolic estrogens and Pauly's reagents was adopted to greatly enhance the SERS signal. BPA display a characteristic Raman band at 1592 cm which can be used for its selective detection. The assay is highly sensitive and has a 1 nM detection limit which is the lowest among the reported semiconductor substrates. Graphical abstract MoS/ZnO MCs SERS substrate broke through the application barrier of semiconductor composite materials in SERS substrates. It also sheds light on a deeper understanding of the charge-transfer based enhancement mechanism.