System and method for photoelectrochemical air purification

An air purification system comprising:

• a housing defining a lumen, a filter attachment region, an inlet, an outlet, and a flow pathway between the inlet and the outlet;
• a filter assembly retained within the lumen intersecting the flow pathway and coupled to the filter attachment region, wherein the filter assembly comprises:
• 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 nanoparticles and a second quantity of crushed nanostructures, wherein the photocatalytic material comprises a homogenous distribution of the first quantity of nanoparticles and the second quantity of crushed nanostructures, wherein the second quantity of crushed nanostructures defines a size distribution, wherein a peak of the size distribution corresponds to a plasmonic resonance frequency, and wherein the ratio of the first quantity to the second quantity by mass is greater than one;
• a photon source coupled to the housing and arranged to illuminate the photocatalytic material with optical radiation, wherein the optical radiation is at least partially visible, wherein the optical radiation defines a wavelength range that overlaps the plasmonic resonance frequency;
• and
• a flow control mechanism coupled to the housing and arranged along the flow pathway, wherein the flow control mechanism is configured to urge airflow along the flow pathway between the inlet and the outlet of the housing.