Ce-Zn MOF derived dandelion-like CeO2-ZnO and rGO nanosheets hybrid for highly sensitive electrochemical detection of dopamine

Low conductivity and slow reaction kinetics are partly responsible limiting the sensing performance of metal-organic-framework (MOF) derived metal oxides, which can be overcome by rational composition and novel microstructural design. In this study, hollow dandelion-like Ce-Zn MOF/reduced graphene oxide (rGO) nanosheets precursor were synthesized by solvothermal reaction and the precursor was annealed to obtain CeO 2 -ZnO/rGO (CZO/rGO). The effects of polyvinylpyrrolidone (PVP), rGO and annealing temperature on its morphology and sensing properties were investigated. The unique morphology of CeO 2 -ZnO provides abundant active sites and large specific surface areas which can improve the ion diffusion efficiency, and the high conductivity of rGO reduces the interfacial resistance and improves the electron transfer rate. The optimized CZO/rGO/ITO electrode achieves a high sensitivity of 17.67 μA·μM -1 ·cm -2 and a limit of detection of 2.1 nM (S/ N = 3) for dopamine (DA) detection. This study broadens the application of MOF derivatives in DA sensing.