▎ 摘 要
Nitrogen-doped graphene oxide monoliths (NGOMs) were readily fabricated by crosslinking graphene oxide (GO) using four different short chain aliphatic amines, i.e., ethylenediamine (EDA), dimethylaminopropylamine (DMPDA), N-isopropylethylenediamine (IPEDA), and triethylenetetramine (TETA). Depending on the structure of the amine crosslinkers, the generated monoliths showed various morphologies with different d spacing, layer thickness, and microspore size. Fourier transform-infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses provided evidence for the formation of covalent C-N or C=N bonds in all cases, indicating that the interaction of GO with amine crosslinkers involved the ring-opening reaction between GO epoxides and amine groups. The formation of both quaternary nitrogen and some nitrogen-containing heterocyclic composition inside the graphene oxide sheet were also suggested. X-Ray Diffraction (XRD) results indicated that the interspatial distance between GO sheets was increased after crosslinking. The fabricated NGOM-TETA demonstrates potential application as an adsorbent material due to its efficient removal of copper ions.