Facile preparation of graphite nanosheets with excellent adsorption property

Abstract Graphene and its derivative (graphene oxide, GO) have lots of important functional applications in various fields. At present, the improved Hummers’ methods are the most important preparation methods used to prepare GO nanosheets in scientific research and industrial preparation. Although many improvement measures of the Hummers’ method have been performed, and some problems still need to be solved. Herein, we develop a facile and green method to prepare nanosheets by exfoliating graphite powders in a dilute sulfuric acid (H2SO4) aqueous solution with hydrogen peroxide (H2O2) as oxidant, and subsequent ultrasonic treatment. The characterization results confirm that graphite nanosheets can be obtained with abundant oxygen-containing functional groups, similar to that of GO. Compared with the precursor, the obtained nanosheets have better adsorption performance, and can be used as adsorbent to remove methylene blue (50 mg/L) from water with removal efficiency of 95.0% and removal capacity of 23.8 mg/g, respectively. These nanosheets can also be used to remove Cd2+ (56.2 mg/L) with removal efficiency of 88.0% and removal capacity of 24.7 mg/g, respectively. The exfoliation mechanism has been analyzed and interpreted as strong oxygen attacking and subsequent ultrasonic stripping. This work provides an efficient preparation method of 2D graphite nanosheets for functional applications such as excellent adsorbent.