The formation of dominant water channels is a serious problem for most oilfields, which results in low sweep efficiency.

Recently, much attention has been directed toward nanofluids’ applications for enhanced oil recovery (EOR). Here, amphiphilic molybdenum disulfide (KH550-MoS₂) nanosheets are synthesized using a hydrothermal approach. The physicochemical properties and EOR potential of ultralow concentration KH550-MoS₂ nanofluids are systematically investigated at Changqing Oilfield (China) reservoir conditions (temperature∼55 °C and salinity∼7.8 × 10⁴ mg/L). Interfacial tension (IFT), wettability alteration and emulsion stability are characterized to evaluate the physicochemical properties of KH550-MoS₂ nanofluids. The results show that ultralow concentration KH550-MoS₂ nanofluid (50 mg/L) can decrease IFT to 2.6 mN/m, change contact angle (CTA) from 131.2° to 51.7° and significantly enhance emulsion stability. Core flooding experiments are conducted to determine the dynamic adsorption loss law and oil displacement efficiency of KH550-MoS₂ nanofluid. Results indicate that the cumulative produced KH550-MoS₂ nanosheets ratio to total injected KH550-MoS₂ nanosheets (CNR) reaches 91.5% during flooding in a low permeability reservoir. Moreover, ultralow concentration KH550-MoS₂ nanofluid can increase oil displacement efficiency by 14% after water driven. This work offers a new amphiphilic nanofluid with high efficiency for EOR. Graphical Abstract