▎ 摘　　要

Biosynthesis of nanoparticles using plant extract is one kind of the effective approach in developing rapid, clean, nontoxic, and eco-friendly technology. In this work, iron nanoparticles/reduced graphene oxide composites (Fe NPs/rGO) were facilely fabricated through one-step method with eucalyptus leaf extract. The synthesized Fe NPs/rGO was investigated by various characterization methods. SEM results disclosed that Fe NPs with regular spherical shape of 70 +/- 10 nm was uniformly dispersed on rGO. A basal plane of rGO with high surface area, providing more load sites for Fe NPs, which was confirmed by TEM. XRD and FTIR results indicated that biomolecules from eucalyptus extract were capped on Fe NPs/rGO. The EDS mapping showed that Fe NPs dispersed evenly on rGO, and XPS further confirmed that Fe NPs/ rGO composite was mainly comprised with Fe NPs and rGO. Furthermore, the biomolecules of eucalyptus leaf extract were identified by GC-MS to confirm that alcohol phenols acted as reducing agent, while alcohol acids and ketones acted as capping agents. In addition, the removal efficiency of Methylene blue (MB) up to 93% with Fe NPs/rGO. This work provides a simple, green cost-effective and environmentally friendly method to fabricate metal/rGO composite. (C) 2019 Elsevier Ltd. All rights reserved.