A container made of a porous material and coated with precious metal nanoparticles is disclosed. The method of making it includes: adding precious metal nanoparticles and intermedium particles to a solution; maintaining the solution at a first temperature; heating a container body made of a porous material at a second temperature; and immersing the container body in the solution wherein the temperature difference between the first temperature and the second temperature causes the precious metal nanoparticles and intermedium particles to permeate into the pores of the container body. The resultant container has precious metal nanoparticles not only attached to its surface but also within its pores.