Magnetic bamboo chars with fluffy graphene surface for efficient dye removal

Magnetic bamboo char (MBC) with fluffy graphene furs was prepared by a catalytic thermal decomposition process. Fe-Bamboo char (Fe-BC) sample was first prepared by impregnating a bamboo char (BC) with iron nitrate solution, followed by catalytic carbonization Fe-BC at 900 °C to obtain MBC. The carbonized Fe-BC sample was embedded with graphene encapsulated iron nanoparticles (GEINs). MBC was then thermally treated in methane at 800 °C. The samples were characterized by SEM, TEM, XRD, and Raman. The results reveal that the surface of MBC grows with graphene furs which consist of hundreds of layers graphene nanoplatelets, these graphene nanoplatelets are connected along the perpendicular direction of the hexagonal; The length of the fluffy graphene furs is around 1–2 μ m. The obtained adsorption results suggested that MBC with fluffy graphene furs can effectively adsorb methylene blue (MB). The magnetic bamboo char with fluffy graphene furs (MBC-GFs) demonstrate an adsorption capacity of 282.6 mg g −1 for MB. Furthermore, it can be magnetic separation to recycle adsorbent. The kinetics of adsorption followed the pseudo-second-order kinetic model, while the Langmuir adsorption isotherm was applicable to describe the equilibrium adsorption process over MBC-GFs. The effect of pH on adsorption was studied in the range of 2 to 10 in BMC-GFs sample and the equilibrium adsorption amounts (qe) of MB onto the MBC-GFs is slightly pH-dependent. The qe values increase with increase of the initial solution pH.