A method of photocatalytic degradation includes contacting a copper hydroxide nitrate/calcium silicate/graphite-phase carbon nitride (Cu.sub.2(OH).sub.3NO.sub.3/CaSiO.sub.3@g-C.sub.3N.sub.4) nanocomposite with a solution including one or more pollutants. The method also includes degrading the pollutants on the nanocomposite and a method of fabrication of the nanocomposite.

A method for synthesizing a Cu.sub.2(OH).sub.3NO.sub.3/CaSiO.sub.3@g-C.sub.3N.sub.4 nanostructure includes mixing a calcium silicate (CaSiO.sub.3), a graphite-phase carbon nitride (g-C.sub.3N.sub.4) and a copper salt in a glycol solvent to form a mixture. The method also includes microwaving the mixture to form the nanostructure having a multi-phase crystalline structure with controlled morphology.

A method for synthesizing a Cu.sub.2(OH).sub.3NO.sub.3/CaSiO.sub.3@g-C.sub.3N.sub.4 nanostructure includes mixing a calcium silicate (CaSiO.sub.3), a graphite-phase carbon nitride (g-C.sub.3N.sub.4) and a copper salt in a glycol solvent to form a mixture. The method also includes microwaving the mixture to form the nanostructure having a multi-phase crystalline structure with controlled morphology.