Following our previous findings that spatial confinement using core@shell cobalt-based catalysts could regulate the product distribution toward desired distillate. We developed a facile solvothermal method to prepare Co3O4@C-mesoporous SiO2 (Co3O4@C-m-SiO2) catalysts with inert C modified surface of mesoporous channel using PVP polymer as carbon source. High-resolution transmission electron microscopy (HRTEM) characterization result, together with the N-2 physisorption, indicated that the Co3O4@C-m-SiO2 catalysts with inert C modified mesoporous channel could be prepared via carbonization of PVP polymer under argon gas instead of calcination and mesoporous silica shell could also be fabricated after inert C modification, and thus higher mesoporous nature contributed to the facile access of the reactant gas to the active Co sites and diffusion of formed product. Hydrogen temperature programmed reduction (H-2-TPR) showed that the degree of reduction for the Co3O4@C-m-SiO2 catalysts were enhanced gradually with increase of C modifier content due to weak Co-C interaction instead of strong Co-silica interaction in the Co3O4@m-SiO2 catalysts. As a result, such inert C modified cobalt-based catalyst with core@shell structure, which possessed rigid porous framework to allow free access of syngas and inhibit mesoporous channel collapsing during F-T reaction, showed the higher catalytic activity and stability due to synergetic effect between higher Co dispersion and reducibility. Moreover, hydrophobic channel of the Co@C-m-SiO2 catalysts with different C modifier content, which were likely favorable to the internal transportation of H2O byproduct and spatial confined effect for the formed hydrocarbon, led to a better selectivity toward C-5-C-18 fraction than that of unmodified Co@m-SiO2 catalysts in the FTS. (C) 2014 Elsevier RV. All rights reserved.