CO₂ adaptive functional materials: Perspectives in geological utilization and sequestration

Against the global backdrop of carbon neutrality, technological revolution, and deep oil development strategies, the advancement of large-scale integrated technologies for CO₂ geological utilization and sequestration (CO₂-GUS) holds strategic significance for safeguarding national energy security and mitigating climate change. Currently, century-scale geological sequestration and utilization of CO₂ remain heavily reliant on simulation and predictive methodologies, underscoring an urgent need to advance collaborative innovation between molecular design strategies and engineering application technologies. This paper focuses on recent progress in this field, systematically reviewing the design strategies of CO₂-responsive gels, self-adaptive foams, nano-bubbles, and supercritical CO₂ thickeners, with particular emphasis on molecular design principles for CO₂ affinity and deep subsurface adaptability. It analyzes the temperature and salt tolerance of CO₂-responsive gels and thickeners, as well as CO₂ mobility control mechanisms, reveals the synergistic mechanism of energy release enhancement and enhanced oil recovery (EOR) via CO₂ nano-bubble bursting, and clarifies the colloidal interfacial behavior of CO₂ self-adaptive foams. Furthermore, this study outlines future directions for advanced atomic force microscopy (AFM) characterization techniques at the molecular and atomic scales in CO₂-GUS applications. It also evaluates the engineering performance of these systems in synergistic CO₂-EOR and sequestration technologies, as well as in integrated CO₂ fracturing-EOR-sequestration processes. Finally, a century-scale deployment framework for CO₂ self-adaptive functional materials in geological utilization and sequestration is proposed, thereby providing a theoretical basis and technical support for the long-term safe management of CO₂.