Controlled electrodeposition of tungsten oxide nanoparticles on MXene nanosheets-framework for ultrasensitive light enhanced detection of dopamine

In this work, a sensitive and efficient light enhanced electrochemical dopamine sensor based on tungsten oxide nanoparticles electrodeposited on MXene nanosheets modified pencil graphite electrode (MXene-WO_x/PGE) was reported. The prepared substrate was carefully characterized with field emission scanning electron microscopy, energy dispersive X-ray analysis, Raman spectroscopy, electrochemical impedance spectroscopy and voltammetry techniques in details. The surface area of MXene-WO_x/PGE was increased 3.75 times in compare with WO_xNPs/PGE proving the role of MXene as a suitable 2D nanomaterials on the electrode surface. The synergistic effect of 2D MXene and tungsten oxide nanoparticles resulted an improved light current response and admirable photocatalytic properties. Linear range, sensitivity and detection limit of the prepared photoelectrochemical sensor for dopamine were reported to be 10-400 nM, 0.028 mA nM^{- 1} and 1 nM respectively. The proposed sensor was utilized for photoelectrochemical detection of dopamine in serum samples with suitable reproducibility, stability and selectivity.