Graphene-Metal Oxides Modified Electrochemical Sensors for Toxic Chemicals

Abstract

This chapter discusses the recent progresses in environmental electrochemistry and its wide capabilities and application towards pollution free environment. Various chemicals including agrochemicals, heavy metals, and other toxic materials polluting the environment can either be treated or transformed to non-toxic elements. Environmental protection and incessant development of people’s value of life are found to be the most important areas of the application of electrochemical sensors in future. A sensor, here, is a chemical-play-tool that converts a chemical data like composition, presence of a particular ion, concentration, chemical activity, and partial pressure into a systematically useful signal. Currently, with new challenges and prospects, the electrochemical sensors have new and wide areas of outlook and applications. The electrochemical biosensor is a simple device that measures electronic current either ionic or by change in conductance carried by the bio-electrodes. Generally, carbon materials are widely used as electrode substrates to make different electrodes owing to its soft properties and renewable for exchange of electrons. Befittingly the arrangement of carbon atoms in graphene enhances its promising applications in several fields. On the other hand, nano materials possess good geometric as well as unique mechanical, physical and chemical properties that significantly encourage applications in medicine, electronics, environmental science and biosensors. In this chapter, the application of graphene- ZnO nano composite material is discussed for analysing the toxic chemicals in the environment and biological samples because of its high sensitivity and good reproducibility. 2-NP. 2-NP r-GO/ZnO/GCE The calibration linear 0.9916) 2-NP nM The detection limit and the sensitivity 0.27 nM and 5.8 μA, mM -1 .cm -2 respectively based on 3N/S (Signal-to-Noise ratio) The present research demonstrated the detection of 2-NP by I-V method using r-GO/ZnO composites modified GCE electrode with very high sensitivity compared to various nanocomposites reported earlier. The synthesis of r-GO/ZnO composites using chemical reduction process is a very good way of based r-GO/ZnO composites for toxic and electro-catalytic materials. These novel nano structures show superior electrocatalytic activity, selectivity, and long-term stability, which can serve as promising electrode material for different electrochemical reactions including detection and detoxification of chemical pollutants in the environment and biological samples.