Electrochemical determination of trichloroacetic acid using an ionic liquid functionalized graphene–AgPd alloy nanoparticle composite modified electrode with the enhancement effect of cetyltrimethylammonium bromide

AgPd nanoparticles were assembled on ionic liquid-functionalized graphene by electrostatic interaction to form a graphene–metal composite. The resulting hybrid nanomaterial was characterized by transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and ultraviolet-visible absorption spectrophotometry. The AgPd nanoparticles were confirmed to be alloy and they were well dispersed on the ionic liquid-functionalized graphene sheets. The hybrid nanomaterial showed striking electrocatalytic activity toward the reduction of trichloroacetic acid (TCA). At the hybrid nanomaterial modified glassy carbon electrode, TCA exhibited a cathodic peak at about −0.65 V (vs. SCE) in pH 7 phosphate buffer solution, which was further enhanced by cetyltrimethylammonium bromide. Under the optimal conditions, the determination of TCA was performed with a linear range of 0.5–50 μM and a detection limit of 0.2 μM (S/N = 3).