We have developed a novel strategy for incorporating NiO nanoparticles into mesoporous Al2O3 with a mean pore size of similar to 12 nm and particle size of similar to 1 mm. Ni-precursor vapor and ambient atmosphere were filled in a closed chamber with mesoporous Al2O3, and the chamber was initially heated at similar to 100 degrees C, at which no chemical reaction between the inorganic precursor, oxygen, water vapor in the atmosphere, and the surface of Al2O3 took place. Next, the temperature of the system was increased to 260 degrees C for deposition of NiO. We found that Ni0 nanoparticles were not only deposited on the surface, but were also incorporated in a 50 mu m-deep region of the mesoporous Al2O3 gel. We also demonstrated high CO oxidation activity and reusability of the deactivated NiO/Al2O3 catalysts prepared by the aforementioned method. These results suggest that our strategy could be widely applicable to the incorporation of various nanoparticles into mesoporous supports. (C) 2016 Elsevier B.V. All rights reserved.