In an aspect, a method for making a metal-containing material comprises steps of: forming a metal-containing hydrogel from an aqueous precursor mixture using a photopolymerization; wherein the aqueous precursor mixture comprises water, one or more aqueous photosensitive binders, and one or more aqueous metal salts; and thermally treating the metal-containing hydrogel to form the metal-containing material; wherein the metal-containing hydrogel is exposed to a thermal-treatment atmosphere during the step of thermally treating; wherein a composition of the metal-containing material is at least partially determined by a composition of the thermal-treatment atmosphere during the thermally treating step.