In this paper, a series of CSs (CSs was the abbreviation of carbon sphere) was synthesized by surfactants-assisted hydrothermal method, and these CSs were used as support to load metal active species for low-temperature oxidation of CO. By adjusting surfactant type and content, hydrothermal time and temperature, the optimal prepared condition of catalyst were achieved: polyvinylpyrrolidone (PVP) content=3%, hydrothermal time = 7 h, and hydrothermal temperature = 180 degrees C. Contrasted Pd-Fe/CSs catalyst with Pd-Fe/CSs-PVP-S (Pd-Fe/CSs-PVP-S was abbreviation for the optimal catalyst) catalyst, it was discovered that CSs-PVP-S owned smaller particle size and higher surface area than CSs. The surface of Pd-Fe/CSs-PVP-S catalyst had rich active oxygen species, more FeO(OH) species and more tetravalent Pd species than the Pd-Fe/CSs catalyst, which vividly demonstrated that the Pd-Fe/CSs-PVP-S catalyst displayed superior activity than Pd-Fe/CSs. (C) 2015 Elsevier B.V. All rights reserved.