The destabilization of gas-liquid foams at elevated temperatures is a critical problem in multiphase flow. This study investigates the underlying physical mechanisms by using a novel SnS₂ quantum dots anchored on MgO nanosheets (SnS₂ QDs/MgO)—modifies the interfacial propeties and bulk fluid properties to arrest these processes in methane foams under high-temperature conditions (80– 120°C). Through systematic variation of nanocomposite concentration (10–100 ppm), an optimal loading of 75 ppm identified as maximizing foam half-life. High-resolution morphological analysis reveals that the nanocomposite refines the foam's microstructure by producing a finer texture with a reduced average bubble size (≈83.21 μm compared to ≈172.58 μm for the base foam) and a significantly increased lamella thickness (≈29.94 μm compared to ≈19.08 μm for the base foam). Interfacial measurements demonstrate that the SnS₂ QDs/MgO reduces gas-liquid interfacial tension and modifies the disjoining pressure within the lamella by forming an interfacial layer whose characteristics are consistent with particle jamming, as quantitatively described in recent literature for nanoparticle-stabilized foams. Furthermore, it alters the rock wettability, shifting capillary forces to favor oil mobilization. Core flooding experiments at 120°C validate the macroscopic efficacy of these microscale physical mechanisms, with the nanocomposite-stabilized foam achieving a final oil recovery of 42.43%—a 14.00 percentage-point increase over foam flooding. This work provides aultiscale physical understanding of foam stabilization, demonstrating a robust strategy for controlling complex fluid interfaces in high-temperature subsurface flows
