Co(OH) ₂ nanosheets decorated Cu(OH) ₂ nanorods for highly sensitive nonenzymatic detection of glucose

Abstract

Co(OH)₂ nanosheets/Cu(OH)₂ nanorods composite electrodes for non-enzymatic glucose detection were fabricated by electrodepositing Co(OH)₂ nanosheets on Cu(OH)₂ nanorods substrate grown directly on the copper sheet via a simple one-step reaction. The Co(OH)₂ nanosheets/Cu(OH)₂ nanorods composite electrode was characterized by scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction and x-ray photoelectron spectroscopy. The glucose sensing performance of the composite electrode was investigated by cyclic voltammetry and chronoamperometry. The composite electrode shows high sensitivity of 2366 µA mM^-1 cm^-2 up to 2 mM with a lower detection limit of 0.17 mM (S/N = 3). The composite electrode is highly selective to glucose in the presence of various substances that always co-exist with glucose in real blood samples. The response of the composite towards human blood serum was in good agreement with that of commercially available glucose sensors, suggesting that a promising electrode material for highly sensitive and selective non enzymatic detection of glucose can be envisioned.