Graphene oxide-monohydrated manganese phosphate composites: Preparation via modified Hummers method

摘要

A modified Hummers method was established to prepare graphene oxide-MnPO4 center dot H2O (denoted as GO-MnPO4 center dot H2O) composites. Findings indicate that the as-formed GO-MnPO4 center dot H2O particles are of a petal-shape and exhibit a uniform size of similar to 1.2 mu m, and they are stable and remain nearly unchanged after 2 day of standing at 30. in air. The formation mechanism was investigated by computer simulations in combination with experimental explorations. The Mn2+ ions obtained by oxidation reaction can be distributed around the oxygencontaining functional groups of GO (especially for hydroxyl) and interact with them via electrostatic forces or coordination bonds. The as-formed GO-Mn2+ dipolar pair can further act as the anchor sites to facilitate the growth of MnPO4 center dot H2O. During the formation of GO-MnPO4 center dot H2O composites, MnPO4 center dot H2O species contributes to promoting the exfoliation of GO sheets. Moreover, the polycrystalline structure of GO-MnPO4 center dot H2O aggregates is destroyed heavily under 450 degrees C, and they can be decomposed to generate reduced GO-Mn2P2O7 (denoted as rGO-Mn2P4 center dot O-7) after 900. treatment in N-2 atmosphere. This methodology made the synthesis of GO-MnPO4 center dot H2O and rGO-Mn2P4 center dot O-7 composites possible and may be further extended to prepare more complicated nanocomposites based on GO sheets for technological applications.