Title : In situ development of silver nanocatalysts at chitosan functionalised graphene oxide for conversion of 2 4 dinitrophenol in water
Abstract:
The discharge of untreated industrial effluents into the environment represents one of the leading causes of pollution on our freshwater ecosystems. Appropriate treatment of the contaminants in these effluents is a feasible approach that can value wastewater and reduce the negative impact on the environment. Among the organic contaminants that have been identified in industrial wastewater, nitrophenols have shown acute toxicity to human health and aquatic life [1]. Several technologies have been reported to treat nitroaromatics in water and these include the noble metal nanoparticle-assisted hydrogenation in the presence of hydrogen-donors. Stabilisation of these nanocatalysts onto supports is a popular strategy that improves their efficiency. Although the performance of noble metal nanocatalysts is laudable in terms of their synergistic action with the support matrix [2], high cost and limited availability are their major downsides [3]. The focus of this presentation is on the development of relatively low-cost materials that could support the in situ nucleation, growth, and stabilisation of Ag nanoparticles in adsorption procedures, without the assistance of a reductant and stabiliser. The simple fabrication of a four-component, graphene oxide/fumaryl chloride/chitosan/Ag NPs (GO-FL-CS-Ag NPs) composite will be described. The pre-synthesized graphene oxide sheets are cross-linked with bio-derived chitosan polymer through ester linkage using fumaryl chloride. Next, the reduction between silver ions and the amino-rich GO-FL-CS is carried out at room temperature under organic solvent-free conditions. The kinetic study for the conversion of the harmful nitrophenols to amino derivatives in water, using the in situ developed Ag NPs at solid supports will be discussed. The presented materials will be systematically characterised using a combination of microscopic and spectrometric techniques. The catalytic reduction route and reusability test will also be presented based upon voltammetric measurements.
This presentation will show that the presence of amino groups within the support structure provides a “green” and simple alternative for the nucleation and anchoring of metal NPs, in the presence of the corresponding cations.
