Synthesis of a three-dimensional interconnected carbon nanorod aerogel from wax gourd for amperometric sensing

The authors describe a method for synthesis of a three-dimensional (3D) interconnected carbon nanorod aerogel (3DICNA) starting from wax gourd (Benincasa hispida) which is a low-cost biomass. The 3D-ICNA possesses unique 3D interconnected and porous nanostructure, with abundant edge-plane-like defective sites, a large specific surface area (823 m2 g-1) and a large pore volume (0.12 cm3 g-1). This makes the material attractive in terms of electrochemical sensing. To validate the feasibility, the voltammetric response towards ferricyanide, hydrogen peroxide (H2O2), acetaminophen, ascorbic acid (AA), dopamine, uric acid and epinephrine was investigated by using a glassy carbon electrode (GCE) modified with 3D-ICNA. The modified GCE shows higher electron-transfer capacity than a conventional GCE. In addition, as an electrochemical sensor for AA or H2O2, the electrode exhibits better analytical performance with lower detection limit [ 3.5 mu M for AA or 0.68 mu M for H2O2 based on 3s/ m criterion (where s is the standard deviation of the blank and m is the slope of the calibration plot)], wider linear range and higher sensitivity (0.14, 0.11 and 0.080 mu A mu M-1 cm-2 for AA or 0.24 and 0.20 mu A mu M-1 cm-2 for H2O2) compared to a plain GCE or a carbon nanotube-modified GCE. The modified GCE exhibits a large potential for the amperometric determination of AA or H2O2 in real samples.