Synthesis of reduced graphene oxide/Co 3 O 4 nanocomposite electrode material for sensor application

A sensitive electrochemical sensor has been developed based on reduced graphene oxide/Co 3 O 4 (rGO/Co 3 O 4 ) nanocomposites (NCs) synthesized by a facile solvothermal method. The developed sensor was used to determine the Dopamine Acid (DA) and Uric Acid (UA). The structure, morphology, band gap and composition of NCs was characterized by powder X-ray diffraction, scanning electron microscope, UV–Vis-Diffuse reflectance, FT-IR, Raman and Energy Dispersive Spectroscopy. rGO/Co 3 O 4 NCs exhibited better electrocatalytic activity for the oxidation of DA and UA in solution with phosphate buffer at pH 7.0. For individual determination, the oxidation peak currents were linearly increased with the concentration of DA and UA in the ranges of 0.5–10 μM and 100 μM–1 mM, respectively. The detection limit of DA and UA was estimated to be 0.176 μM and 1.31 μM, respectively, with ( S / N = 3). The fabricated modified electrode displayed an excellent anti-interference ability against 100-fold higher concentration of potential interferent species and metal ions with good stability and reproducibility. Results show that the developed sensor has a potential to determine the target analytes in real samples with satisfactory efficiency.