Muffler including an internal photocatalyst and a light source

A muffler, comprising:

• a muffler housing having an exhaust gas inlet port adapted for securing to an exhaust pipe of an automobile so that exhaust gases from an internal combustion engine of the automobile are directed through the muffler housing from the exhaust gas inlet port to an exhaust gas outlet port;
• a plurality of rigid surfaces within the muffler housing, wherein the plurality of rigid surfaces form an exhaust gas pathway including a plurality of turns and leading from the exhaust gas inlet port to the exhaust gas outlet port, and wherein at least a portion of the plurality of rigid surfaces is formed by a transparent substrate;
• a photocatalyst coating secured to an area of the plurality of rigid surfaces, wherein the photocatalyst coating includes a transparent binder layer secured to the surface of the transparent substrate and a transparent semiconductor photocatalyst layer secured to the transparent binder layer;
• and
• a light source secured to the muffler housing and positioned to direct light onto the photocatalyst coating, wherein the exhaust gases come into contact with the photocatalyst coating and reactive species generated by the photocatalyst coating decompose one or more pollutants in the exhaust gas.