Au nanocages for highly sensitive and selective detection of H2O2

Au nanocages (AuNCs) were synthesized by a simple one-pot method without the use of any solid templates or Au seeds. The structure of the as-prepared AuNCs was characterized by SEM, TEM, EDS and XRD. For their good electrochemical properties and large surface-to-volume ratio, the AuNCs were utilized to modify glassy carbon electrode (GCE) directly for nonenzymatic detection of H2O2. Electrochemical experiments showed that the AuNCs displayed high electrocatalytic activity towards the reduction of H2O2 and obtained a wide linear range from 0.5 mu M to 5.8885 mM (R = 0.9993) with a detection limit down to 0.1 mu M (S/N = 3). The sensitivity of the H2O2 sensor was as high as 273.83 mu A mM(-1) cm(-2). The sensor also exhibits good anti-interference ability to electroactive molecules, including uric acid, ascorbic acid, glucose, ethanol, and glycine. Moreover, the operating simplicity and low expense of fabrication made this electrode more attractive. (C) 2011 Elsevier B.V. All rights reserved.