Facile synthesis of porous bimetallic alloyed PdAg nanoflowers supported on reduced graphene oxide for simultaneous detection of ascorbic acid, dopamine, and uric acid.

Porous bimetallic alloyed palladium silver (PdAg) nanoflowers supported on reduced graphene oxide (PdAg NFs/rGO) were prepared via a facile and simple in situ reduction process, with the assistance of cetyltrimethylammonium bromide as a structure directing agent. The as-prepared nanocomposite modified glassy carbon electrode (PdAg NFs/rGO/GCE) showed enhanced catalytic currents and enlarged peak potential separations for the oxidation of ascorbic acid (AA), dopamine (DA), and uric acid (UA) as compared to those of PdAg/GCE, rGO/GCE, commercial Pd/C/GCE, and bare GCE. The as-developed sensor can selectively detect AA, DA, and UA with a good anti-interference ability, wide concentration ranges of 1.0 μM-2.1 mM, 0.4-96.0 μM, and 1.0-150.0 μM, respectively, together with low detection limits of 0.057, 0.048, and 0.081 μM (S/N = 3), respectively. For simultaneous detection of AA, DA, and UA, the linear current-concentration responses were observed from 1.0 μM-4.1 mM, 0.05-112.0 μM, and 3.0-186.0 μM, with the detection limits of 0.185, 0.017, and 0.654 μM (S/N = 3), respectively.