Abstract
Molybdenum disulfide (MoS2) screen-printed working electrodes were developed for dopamine (DA) electrochemical sensing. MoS2 working electrodes were prepared from high viscosity screen-printable inks containing various concentrations and sizes of MoS2 particles and ethylcellulose binder. Rheological properties of MoS2 inks and their suitability for screen-printing were analyzed by viscosity curve, screen-printing simulation and oscillatory modulus. MoS2 inks were screen-printed onto conductive FTO (Fluorine-doped Tin Oxide) substrates. Optical microscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) analysis were used to characterize the homogeneity, topography and thickness of the screen-printed MoS2 electrodes. The electrochemical performance was assessed through differential pulse voltammetry. Results showed an extensive linear detection of dopamine from 1 µM to 300 µM (R2 = 0.996, sensitivity of 5.00 × 10-8 A μM-1), with the best limit of detection being 246 nM. This work demonstrated the possibility of simple, low-cost and rapid preparation of high viscosity MoS2 ink and their use to produce screen-printed FTO/MoS2 electrodes for dopamine detection.