h i g h l i g h t s • Chitosan/montmorillonite bionanocomposites, prepared in liquid phase are characterized.

Chitosan/bentonite (CSBt) composites beads were prepared by dropwise of a solution containing chitosan and bentonite to an alkaline NaOH solution. Fourier Transform Infrared Spectroscopy, X-ray diffraction analysis, Xray photoelectron spectroscopy, XPS and Brunauer-Emmett-Teller BET analysis have been used to provide new insights on the composition and morphology of CSBt composites beads surface. In this study, inverse gas chromatography (IGC) was implemented to characterize physico-chemical properties of CSBt composites surface. IGC at infinite dilution (IGC-ID) was used to understand the effect of CS on dispersive component of the surface energy of the bentonite. The increasing amount of CS leads to significantly decrease of Bt γ s d emphasizing the Bt coating with CS. The IGC at finite concentration (IGC-FC) was also implemented allowing us to reach several parameters such as: specific surface area with organic probes and the distribution functions of the adsorption energy sites on the solid surface. In this case, the most significant decreases were observed in the specific surface area obtained with the octane and isopropanol probes. The distribution function of the adsorption energy sites obtained with isopropanol revealed the decrease in the number of the high energy sites with increase of CS/Bt mass ratio.

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This study depicts the electrochemical synthesis of nanocomposites basede on Polyaniline nanorods wrap with reduced graphene oxide (PANI-rGO) on ITO substrates. Synthesis of PANI-rGO nanocomposites was elaborated by the incorporation of rGO in PANI thin films during electropolymerization in the presence of sulfuric acid. The synthesis of reduced graphene oxide was by modification on the well-known Hammer's method. The thin films nanocomposites were characterized by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (FESEM), UV–Visible and electrochemical photocurrent spectroscopy. FESEM revealed the formation of PANI nanorods with diameters between 50 and 150 nm. The XPS was employed to confirm the compositions of PANI-rGO nanocomposites. From photoelectrochemical results, the generated photocurrent was improved in the presence of rGO in PANI Nanorods. Whereas, experimental findings show that the introduction of rGO into PANI improved the photo response from 7 µA.cm-2 to 13 µA.cm-2. Integration of 3D rGO in PANI results in better photocatalytic performance for the degradation of Congo Red. The enhanced photocatalytic activity with presence of rGO revealed the good potential of PANI-GO nanocomposites for dye degradation. The effective removal of congo red up to 90% has been observed in acidic medium and is acceptable results compared to the surface area of the substrate. At optimum conditions, also the nature of the antibacterial activities has been investigated by ITO/PANI and ITO/PANI-rGO thin films, and the results have showed exhibited antibacterial activity against the growth of E.coli gram-negative bacteria.