*2.1.5 Hybrid nanocomposites*

One of the hybrid nanocomposites is reduced graphene oxide-magnetite nanoparticle (RGO-Fe3O4 NP) and its synthesis is described below according to the literature [12].

Reduce graphene oxide magnetite nanoparticle (RGO-Fe3O4 NP) hybrid was synthesized by alkaline reduction. For this purpose, the powder was redispersed in the 0.5 mg mL−1 graphene oxide (GO) suspension. Citric and ascorbic acids were added and the mixture was stirred at 55°C (12 hours). 1 M NaOH was added and the mixture It was stirred again at 95°C (6 hours). After centrifugation at 10000 rpm (RCF = 1118 x g), the solid is filtered, washed, and dried in vacuum during 24 hours [12].
