Fig. 1: High-efficiency extraction of trace amounts of gold.
From: Highly efficient and selective extraction of gold by reduced graphene oxide
a Schematic of the extraction process using rGO. After mixed with gold ion (10 ppm) for 12 h, rGO suspension gradually changed its color from black to brown. The bottom panels are the optical images of rGO films deposited from rGO nanosheets before (black) and after gold extraction (gold). Scale bar: 20 μm. b Extraction capacity as a function of gold concentration after 24 h. The inset plots the extraction efficiency measured for 10 ppm solutions at different pH. c Extraction capacity as a function of time for a 10 ppm gold solution. Inset: Extraction from different solutions after 10 min. Dashed lines, guides to the eye. All the experiments were performed at 25 °C. All the error bars in this figure represent the standard deviation.
