Influence of temperature on structure, morphology, and magnetic property of graphene–MnFe2O4 nanocomposites synthesized by a combined hydrothermal/co-precipitation method

Combination of co-precipitation and hydrothermal methods is a promising route to synthesize various materials. Herein, we synthesized reduced graphene oxide/manganese ferrite (rGO/MnFe 2 O 4 ) nanocomposites through combining a co-precipitation reaction of Mn 2+ and Fe 3+ ions in GO solution with subsequent hydrothermal treatment at different temperatures (80, 130, and 180 °C). The resulting rGO/MnFe 2 O 4 nanocomposites were characterized using X-ray diffractometry, Fourier-transform infrared spectroscopy, scanning and transmission electron microscopy, and magnetic measurements at room temperature. The influence of hydrothermal temperature on structural, morphological, magnetic and As(III) adsorption properties of rGO/MnFe 2 O 4 nanocomposites was studied. Increasing hydrothermal temperature leads to better crystallinity, magnetic properties, and As(III) adsorption capacity. At the hydrothermal temperature of 180 °C, the resulting rGO/MnFe 2 O 4 nanocomposites exhibited a crystalline size of 37.2 nm, saturated magnetization of 22.7 emu/g, and As(III) removal efficiency of 83% at neutral pH (pH ≈ 7).