Recent progress in fluorescent carbon dots in petroleum exploitation: Synthesis, properties and applications

In recent years, carbon dots (CDs) have emerged as one of the most promising candidates in various fields (e.g., biomedicine, optoelectronic devices, and agricultural technology) due to their superior properties (e.g., nanoscale size, large specific surface area, and fluorescent properties). However, the application of CDs in the petroleum field has not been fully summarized. This review aims to provide a comprehensive overview of the recent advances in the application of CDs for petroleum extraction and transportation. This review gives a discussion on the synthesis and modification strategies of CDs (e.g., laser ablation, arc discharge, electrochemical oxidation, solvothermal, hydrothermal, microwave-assisted, pyrolysis, template, and magnetic hyperthermia). We then expand the scope to discuss the optical properties of CDs, such as large Stokes shifts and high quantum yields. Finally, we critically discuss the performance of CDs in petroleum extraction and transportation applications, including fluorescence tracing, enhanced original recovery rate, sensing, oil-water/gas separation, corrosion inhibition, and scale prevention. Overall, CDs demonstrate significant application potential in the petroleum field (e.g., oil extraction and transportation). The present challenges (e.g., large-scale production and environmental stability) and future prospects (e.g., AI assistance and usage of multi-effect agents) are also discussed to expand its widely application. This review highlights the high potential of various CDs in petroleum exploitation applications, which can provide guidance for the application of CDs in oilfield production.