System and method for photoelectrochemical air purification

An air purification system comprising:

• a filter assembly comprising:
• a substrate comprising a fibrous media, and
• a photocatalytic material disposed on the substrate, wherein the photocatalytic material is comprised of a first quantity of crushed nanostructures and a second quantity of nanoparticles, wherein the crushed nanostructures consist essentially of a metal oxide photocatalyst, wherein the nanoparticles are substantially spherical;
• and
• a photon source arranged to illuminate the photocatalytic material with optical radiation, wherein the optical radiation defines a wavelength range comprising a minimum wavelength greater than 280 nanometers.