Silver nanoparticles stabilized by nanocellulose as a sensing probe for mercury (II) detection and their response with iron (III) interference

This research focuses on the application of nanocellulose-stabilized silver nanoparticles (AgNPs) as a colorimetric sensing probe for mercury (II) detection. For this purpose, cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) were employed with dual functions: a stabilizing agent and a dispersing matrix. The chemical and structural properties of the samples were analysed by various techniques such as XRD, FTIR, TEM and UV–Vis Spectroscopy. Due to different morphologies and surface functional groups in each type of nanocellulose, their effects on the AgNP formation as well as their response against mercury (II) ions were studied. It was discovered that the AgNPs stabilized by both types of nanocellulose can provide high sensitivity and selectivity towards mercury (II) ions. However, some interference caused by iron (III) ions was observed. This interference could be significantly reduced if the CNFs were employed during the AgNP preparation. Therefore, the advantage of using the CNFs as a stabilizing agent as well as a dispersing matrix will be discussed in detail. Furthermore, the possibility of fabrication into solid-state platforms (nanopapers) and response to mercury (II) ions will be demonstrated.