Red Mud-Reduced Graphene Oxide Nanocomposites for the Electrochemical Sensing of Arsenic
Sujit Deshmukh, Debosmita Banerjee, Gourav Bhattacharya, Sam J. Fishlock, Anjan Barman, James McLaughlin, Susanta Sinha Roy
Abstract
This work demonstrates the applicability of red-mud-reduced graphene oxide (RM-rGO) nanocomposites (NCs) for the reliable and selective electrochemical (EC) detection of arsenic. The new NC material shows excellent anti-interference activity toward arsenic (As3+) ions with the cooccurrence of other common cations (Cd2+, Cr2+, Zn2+, Pb2+, and Hg2+). Especially, the NC is exceptionally selective for As3+ ions in the presence of Cu2+ ions, which is stated to be the main interfering agent in the EC detection of As3+. Under optimal experimental conditions, the new NC displays a high sensitivity (2.49 μA ppb–1) as well as a very low detection limit (0.07 ppb) toward As3+ detection. This excellent EC performance of the composite is accounted for by the high adsorption proficiency of hematite (Fe2O3)-phase-rich red mud nanoparticles and enhanced electron-transfer kinetics due to the presence of rGO.