Abstract
A nanohybrid of polyaniline grafted graphene oxide@WO3 (PANI-g-rGO@WO3) was prepared by oxidative polymerization of aniline in the presence of tungsten oxide and reduced graphene oxide. The physicochemical characterization of PANI-g-rGO@WO3 was done by FESEM, X-ray diffraction microscopy, FTIR, UV-Vis spectroscopy, thermogravimetric analysis and XPS. The composite was analyzed for hazardous metal selectivity and was found to be highly sensitive for trivalent chromium (Cr3+). For potential trivalent chromium (Cr3+) cation sensor development, the PANI-g-rGO@WO3 nanocomposite was deposited on a flat silver electrode (AgE, surface area, 0.0216 cm(2)) with conducting binders coating to give a sensor with a fast selective response towards trivalent chromium cations in the liquid phase. The sensor also exhibits good sensitivity, long-term stability, and enhanced electrochemical responses. The calibration plot is linear (r(2) = 0.9815) over a 0.1 nM to 0.01 M Cr3+ concentration range. The sensitivity is similar to 4.4251 mu A mM(-1) cm(-2) and the detection limit is 0.031 +/- 0.010 nM (signal-to-noise ratio, at a SNR of 3). The development of a sensitive sensor for hazardous and carcinogenic chromium cations is also commenced using the PANI-g-rGO@WO3 nanocomposite and the I-V method for promising potential future applications in the environmental and healthcare fields.