Simplified synthesis of silver nanoparticles on graphene oxide and their applications in electrocatalysis.

In this work the possibility was investigated to synthesize in-situ silver nanoparticles (AgNP) on graphene oxide (GO) surface without commonly used additional reducing or alkalizing agents or increased temperature. Using diverse microscopic (AFM, TEM) and spectroscopic methods, it was proved that very small AgNPs were formed on GO by simple incubation for 2 hours a mixture of GO dispersion and AgNO3. The prepared nanomaterial (GO_Ag) was also assessed using electrochemical methods and it exhibited electrochemical behavior similar to GO_Ag nanomaterial prepared with a help of citric acid as a reducing agent. Furthermore, it was found that i) electrochemical reduction of the GO_Ag on electrode surface decreased the voltammetric response even though this step has increased the surface conductivity and ii) GO_Ag can be employed for sensing of chlorides with detection limit of 79 M and a linear range up to 10 mM. It could also provide electrochemical response toward chloroacetanilide herbicide metazachlor. Hence, the reducing capabilities of GO were proved to be applicable for in-situ synthesis of metal nanoparticles with the highest possible simplification and the as-prepared nanomaterials could be employed for fabrication of different electrochemical sensors.