Magnetically recoverable Fe3O4/graphene nanocomposite towards efficient removal of triazine pesticides from aqueous solution: Investigation of the adsorption phenomenon and specific ion effect.

Spillage of effluents containing high concentration levels of pesticides into water has been considered as one of the serious environmental problems. In this study Fe3O4/reduced graphene oxide (rGO) nanocomposite has been efficiently utilized for the adsorption of five harmful pesticides namely ametryn, prometryn, simazine, simeton and atrazine in an aqueous medium. Electrostatic interaction between the pesticides and Fe3O4/rGO nanocomposite was analyzed by the zeta potential analysis, which is strongly related to the adsorption capacity of the adsorbent. The kinetics parameters of adsorption followed the pseudo second-order linear model. The adsorption isotherm studies show that, the maximum adsorption capacity of 54.8 mg g-1 is achieved at pH 5 and it was enhanced in the presence of different ions (Mg2+, Ca2+, Na+ and SO42) and maximum (63.7 mg g-1) for ametryn adsorption was found in seawater medium. Thermodynamic parameter shows that, the adsorption process is physisorption and spontaneity in nature. The mechanism of the adsorption process was established by the DRIFT spectroscopy analysis. Efficient adsorption (93.61%) of pesticides was observed due to electrostatic, hydrophobic and π-π interactions of composite towards the heterocyclic conjugation of pesticide molecules. Further, Fe3O4/rGO nanocomposite was easily and rapidly separated from an aqueous medium using the external magnet for reuse and 88.66% adsorption efficiency was observed up to seven cycles.

Correction: Reduced graphene oxide nanosheets decorated with Au-Pd bimetallic alloy nanoparticles towards efficient photocatalytic degradation of phenolic compounds in water.

Correction for 'Reduced graphene oxide nanosheets decorated with Au-Pd bimetallic alloy nanoparticles towards efficient photocatalytic degradation of phenolic compounds in water' by Gitashree Darabdhara, et al., Nanoscale, 2016, 8, 8276-8287.

Reduced graphene oxide nanosheets decorated with Au-Pd bimetallic alloy nanoparticles towards efficient photocatalytic degradation of phenolic compounds in water.

Reduced graphene oxide nanosheets decorated with Au-Pd bimetallic alloy nanoparticles are successfully prepared via a chemical approach consisting of reducing the metal precursors using ascorbic acid as reductant at an elevated temperature. The prepared nanocomposite is employed as a photocatalyst for the degradation of organic contaminants such as phenol, 2-chlorophenol (2-CP), and 2-nitrophenol (2-NP). The complete degradation of phenol is achieved after 300 min under natural sunlight irradiation whereas the degradation of 2-CP and 2-NP is completed after 180 min. The activity of the photocatalyst is evaluated considering several parameters such as the initial phenol concentration, the photocatalyst loading, and the pH of the solution. The degradation kinetics of all the compounds is carefully studied and found to follow a linear Langmuir-Hinshelwood model. Furthermore, the reusability of the photocatalyst is successfully achieved up to five cycles and the catalyst exhibits an excellent stability.