Abstract

Synthesis of nanoparticles (NPs) that can withstand high temperature and high salinity (HT-HS) is a big
challenge in the research community. A novel strategy to synthesize stable nanoparticles under harsh
environment (HT-HS) is proposed in this work by using the synergistic effect of a surfactant mixture.
Long-term stable iron oxide nanoparticles at HT-HS conditions were produced and stabilized by two
different surfactant classes, i.e. sulfonate surfactant for high temperature resistance and ethoxylated
alcohol surfactant for high salinity resistance. The results prove that the new strategy could be used for
production of stable NPs which is suitable for enhanced oil recovery application.