Fabrication and characterization of graphene oxide-chitosan-zinc oxide ternary nano-hybrids for the corrosion inhibition of mild steel.

In this study, graphene oxide-chitosan (GO-CS) and graphene oxide-chitosan-ZnO (GO-CS-ZnO) hybrids were synthesized in order to examine the effectiveness of hybridization in enhancing the corrosion inhibition activity of graphene oxide (GO). In this way, the synthesized GO and nano-hybrids were firstly characterized by using FTIR, UV-Vis, FE-SEM, AFM, TEM and subsequently were studied in term of corrosion inhibition. Our primary results indicated that, single-layer GO, GO-CS hybrids and also GO-CS-ZnO ternary nano-hybrids were appropriately synthesized. The corrosion inhibition results demonstrated superior performance of GO-CS hybrids than pure GO. In addition, GO-CS-ZnO ternary nano-hybrids revealed the highest corrosion inhibition activity compared with all nano-materials studied here. The corrosion inhibition efficiency of GO (η = 42.35%) was enhanced to 83.81% and 85.61% for GO-CS and GO-CS-ZnO nanocomposites in 500 ppm conc., respectively. Generally, our results demonstrated that hybridization strategy successfully promoted the corrosion inhibition efficiency of GO. Furthermore, Langmuir isotherm was used in three methods (PDP, EIS and LPR) to study the adsorption of synthesized nano-materials on mild steel.

Investigating the best strategy to diminish the toxicity and enhance the antibacterial activity of graphene oxide by chitosan addition.

The main objective of this work was to find a way to increase the bio-applicability of graphene oxide (GO) nanoparticles. In this way, various kinds of graphene oxide-chitosan (GO-CS) nano-hybrids were synthesized through attachment of different kinds of chitosan (CS) structures with GO. Subsequently, they were assessed in terms of structural characterization, antibacterial activity and cytotoxicity to obtain a hybrid structure representing the highest bactericidal and biocompatibility performance. Our results revealed that the single-layer GO and also three different kinds of GO-CS nano-hybrid structures (pristine powder, spherical and nano-fibrilar network structures) were successfully synthesized. Antibacterial activity results indicated superior antibacterial activity of nano-hybrids compared to the pure GO. In addition, it was observed that the attachment of CS to GO interestingly reduced the cytotoxicity effect of GO and even caused cell proliferation in some samples. Furthermore, the antibacterial and bio-safety properties of different hybrids were compared and suggestive mechanisms for their particular performances were proposed.