▎ 摘　　要

In this paper, an innovative polyoxyethylated graphene oxide-based nanofluid (P-GO-O) for enhanced oil recovery was prepared. Transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FTIR), Raman spectra, thermogravimetric analysis (TGA), and UV-vis spectra analysis were used to characterize the P-GO-O nanosheets. Moreover, zeta potential, temperature resistance, and salinity tolerance were evaluated to determine the dispersion stability of the P-GO-O nanofluid. The zeta potential of P-GO-O in deionized water was-39 mV, and the P-GO-O nanofluid exhibited excellent high temperature and high salinity resistance. Benefiting from its structure, the P-GO-O nanofluid was capable of lowering the oil-water interfacial tension to 12.2 mN/m and changing the oil-wet surface to the water-wet surface. In the oil displacement test, the oil recovery ratio of P-GO-O nanofluid (17.2%) was higher than the GO-O (octadecylaminated graphene oxide) nanofluid (6.7%), which was attributed to its better stability and wettability alteration. These results indicated that the P-GO-O nanofluid had the potential for enhanced oil recovery (EOR) application. (c) 2021 Elsevier Ltd. All rights reserved.