Functionalization of carbon nanowalls by plasma jet in liquid treatment

Submerged in liquid plasma treatment is a new approach for nanomaterials functionalization. This paper presents a surfactant free method for functionalization of graphene nano-platelets derived from carbon nanowalls through plasma jet treatment of their water suspensions. The untreated and under-liquid plasma treated suspensions were characterized in terms of their UV-Vis absorption, zeta-size, zeta-potential, pH, and conductivity. Investigation of dried material revealed that the graphene nano-sheets morphology and structure have been preserved, showing also new oxygen functional groups bonded to the carbon network after in liquid plasma treatment. The results demonstrate the efficiency of this technique in changing the properties of carbon nanowalls suspensions and also in getting functionalized multilayered graphene sheets

Improving the Voltammetric Determination of Hg(II): A Comparison Between Ligand-Modified Glassy Carbon and Electrochemically Reduced Graphene Oxide Electrodes

A new thiosemicarbazone ligand was immobilized through a Cu(I)-catalyzed click reaction on the surface of glassy carbon (GC) and electrochemically reduced graphene oxide (GC-ERGO) electrodes grafted with phenylethynyl groups. Using the accumulation at open circuit followed by anodic stripping voltammetry, the modified electrodes showed a significant selectivity and sensibility for Hg(II) ions. A detection limit of 7 nM was achieved with the GC modified electrodes. Remarkably, GC-ERGO modified electrodes showed a significantly improved detection limit (0.8 nM), sensitivity, and linear range, which we attribute to an increased number of surface binding sites and better electron transfer properties. Both GC and GC-ERGO modified electrodes proved their applicability for the analysis of real water samples