The three-dimensional self-assembly Eu3+-graphene composite materials are synthesized through a one-pot hydrothermal reaction under 180°C. The obtained samples are analyzed through powder X-ray diffraction, scanning electron microscope, and transmission electron microscopy. The results show that each sample has porous structure and no independent Eu3+agglomerates. Raman spectrum and Fourier transform infrared spectrum analyses indicate Eu3+is well complexed with graphene through oxygen-containing groups.The...