A method includes mixing a dopant salt of at least one of cobalt, nickel, zinc, and scandium with a silicate, in a solvent, to form a first solution. The method includes mixing the first solution with a solvent mixture to form a second solution. The method further includes mixing the second solution with an acid to form an acid solution. The method further includes adding a catalyst and a polymer to the acid solution to form the doped PCM. The doped PCM includes the catalyst, the polymer, at least one of cobalt, nickel, zinc, and scandium, and SiO2.