A nanostructural catalyst with long-term durability under harsh conditions is very important for an outstanding catalytic performance. Herein, a new ultrastable PtCo/Co3O4-SiO2 nano-catalyst was explored to improve the catalytic performance of carbon monoxide (CO) oxidation by virtue of the surface active lattice oxygen derived from strong metal-support interactions. Such a structure can overcome the issues of CO3O4-SiO2 inactivation by water vapor and the Pt inferior activity at low temperature. Further, Co3O4-SiO2 nanosheets endow superior structure stability under high temperatures of up to 800 degrees C, which gives long-term catalytic cyclability of PtCo/Co(3)O4-SiO2 nanocomposites for CO oxidation. Moreover, the large specific surface areas (294 m(2) g(-1)) of the nanosheet structure can expose abundant surface active lattice oxygen, which significantly enhanced the catalytic activity of CO oxidation at 50 degrees C over 30 days without apparent aggregation of PtCo nanoparticles after 20 cycles from 50 to 400 degrees C. It can be expected to be a promising candidate as an ultrastable efficient catalyst.