@article{Wu2023, 
author = {Yining Wu and Lisha Tang and Mengjiao Cao and Li Li and Kai Liu and Demin Kong and Qingshan Zhao and Xu Jin and He Liu and Caili Dai},
title = {Facile and controllable synthesis of amino-modified carbon dots for efficient oil displacement},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {5},
pages = {6048-6056},
keywords = {carbon dots, polymerization, enhanced oil recovery, adhesion force, amino-modification},
url = {https://www.sciopen.com/article/10.1007/s12274-022-4527-8},
doi = {10.1007/s12274-022-4527-8},
abstract = {Zero-dimensional (0D) carbon dots exhibit excellent potential as a new oil-displacing agent for unconventional reservoir development. However, the difficulty in size/surface properties control and unclear mechanism hinder their further applications. In this study, amino-modified carbon dots (am-CDs) for oil displacement were facilely synthesized through the rapid polymerization of D-glucose (D-Glc) and 3-aminopropyltriethoxysilane (APTES). The size of am-CDs could be precisely controlled by the reaction condition and quenching achieved by adjusting the pH value to neutral. The surface amine groups endow am-CDs with excellent hydrophilicity and dispersion stability. The 0.30 wt.% nanofluid based on am-CDs with an average size of 2.6 ± 0.040 nm showed remarkable oil recovery efficiency (54.09%) without the addition of surfactant. The oil recovery efficiency of am-CDs is much higher than those of water flooding (30.25%), nano-SiO2 flooding (36.45%), and amino-free carbon dots (af-CDs) flooding (37.80%). Experimental and theoretical results reveal that am-CDs can be favorably adsorbed on the core surface to modulate the micro-scale wettability, changing the surface from oil-wet to relatively uniform water-wet. Meanwhile, am-CDs can effectively reduce the adhesion force between alkanes and sandstone surfaces, contributing to oil droplets peeling off and oil displacement. This study provides a new strategy for developing efficient carbon dots-based nanofluids for enhanced oil recovery.}
}