**4. Conclusions**

The binding energies of alkylamines, silanes, and haloalkanes were compared, and the most stable binding was found for alkylamines. Using this substance as the object of the study, it was found that the grafted nanoparticles were uniformly dispersed in the aqueous solution without agglomeration. The lipophilic end aggregated towards the center of the molecule, showing a dispersion characteristic different from that of conventional surfactants, which form micelles in solution. After surface grafting of graphene oxide, there are a large number of polar hydroxyl groups on the surface layer, which exhibit a strong hydrophilicity, while a large number of alkyl groups exist on one side, showing strong lipophilicity. Unlike conventional surfactants, a single NGO can exhibit the characteristics of multiple surfactant molecules at the oil–water interface.

The simulations show that there is a self-aggregation phenomenon of NGOs at the oil–water interface, specifically the two processes of transport to the oil–water interface and regular at the oil–water interface. After these two stages, a disordered monolayer interfacial film can be formed at the oil–water interface, and the interfacial film can make the oil–water interface irregular, improving the carrying capacity of water to the oil phase. After the addition of NGO nanoparticles, the increase in temperature reduces the free energy of the interfacial layer, which reduces the resistance between the nanoparticles and the water phase, and the NGOs can be dispersed in the oil–water interface faster, thus accelerating the decrease in the interfacial tension between oil and water. Less energy is required at the injection end, thus making it easier to displace oil drops in small pores and oil films adsorbed on rock surfaces in tertiary oil recovery.

**Author Contributions:** Conceptualization, J.W. and S.T.; methodology, S.T.; software, S.T.; validation, X.W., Y.H. and Y.F.; formal analysis, S.T.; investigation, Q.X.; resources, X.L.; data curation, X.L.; writing—original draft preparation, S.T.; writing—review and editing, S.T.; visualization, J.W.; supervision, J.W.; project administration, J.W.; funding acquisition, J.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** The APC was funded by [Wang, J.].

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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